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  Taarik Hasan has added a new cover photo.

  

  • September 2, 2021

  • Badhon Ahmed likes this.
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  Abhay Sunny is now friends with Taarik Hasan.

  • July 4, 2021
• 
  Taarik Hasan commented on Fatima Ahmed's classified listing.

  

  Adam's Brunoise Dice - $5 Physics Quiz

  Adam's Brunoise Dice - $5 physics quiz
   
  
  Adam Petropoulos recently got admitted to the culinary institute named Le Monde in Athens, Greece. His career goal was to become a chef.  He loved food!  He wanted to learn the art of flavor...

  • June 21, 2021

  • Sourav Chowhan likes this.
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    Khadeeza Afruz Shammee Pascal's principle of pressure describes this knife phenomenon. As a scalar physical quantity ,pressure is defined as the force per unit area applied perpendicular to the surface which it is applied .
    The elementary mathematical expression for pressure...  morePascal's principle of pressure describes this knife phenomenon. As a scalar physical quantity ,pressure is defined as the force per unit area applied perpendicular to the surface which it is applied .
    The elementary mathematical expression for pressure is giving by ,
    P = F/A
    Here, P is the pressure , F is the force acting perpendicular to the surface to which this force is applied and A is the area of the surface .
    The same force applied by a sharp knife with a smaller area of contact will exerts a much greater pressure than a blunt knife having a considerable larger area of contact .
    Once a blunt knife is through the object (vegetable or other food), there is a greater chance for the pressure to lead to slippage, skidding and injury. A sharp knife can cut using the edge of the e knife with a safer slicing. Rather, cuts from sharper knives can actually heal more easily than those from dull knives. A sharp knife is a safer knife than a dull knife.  less

    • June 25, 2021
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    Aria Hossain In physics force=pressure/area. In order to cut food, you have to exert force. According to the equation, force is directly proportional to pressure. A blunt knife has more area around the cutting edge than a sharp knife. So a blunt knife requires more...  moreIn physics force=pressure/area. In order to cut food, you have to exert force. According to the equation, force is directly proportional to pressure. A blunt knife has more area around the cutting edge than a sharp knife. So a blunt knife requires more pressure for the same amount of force to be exerted, as the pressure applied increases the chances of the knife slipping and cutting Adam's hand increases. Similarly, a sharp knife would require less pressure to be applied for the same amount of force to be exerted, this not only allows Adam to cut through the food but also prevents the knife from slipping and cutting his hand.  less

    • June 26, 2021
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    Abdullah Julaybib Firstly, you’ll need more pressure to use a blunt knife.
    P=F/A, for a fixed area, force is directly proportional to pressure. If the
    area of a blunt and a sharp knife is same, then doubling the pressure on blunt
    knife means doubling the force....  moreFirstly, you’ll need more pressure to use a blunt knife.
    P=F/A, for a fixed area, force is directly proportional to pressure. If the
    area of a blunt and a sharp knife is same, then doubling the pressure on blunt
    knife means doubling the force.
    
    Secondly,F= {m(v-u)}/t
    
    Assume, two knives have same mass and you take same amount of time to cut. As
    you start from a zero velocity, that means u=0. Ultimately you end up giving
    much more velocity to the blunt than sharp one. So, if you accidentally slip
    while cutting, blunt will hit your finger faster, which might cause a serious
    injury. Sharp knife will have less velocity, which has multiple advantages:
    bringing the sharp knife to rest is easier than blunt one. If you slip, sharp
    knife won’t hit so fast. It may cause a
    little scratch, or you’ll be lucky to stop the sharp knife as soon as it touches your skin (blunt one
    would cause a deep scar).
    
    
    For same time duration, point of contact (finger and knife)
    faces two different momenta. As a result,...    less

    • June 26, 2021
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    Abhay Sunny Pressure= force/area, area of sharp knife is less than area of blunt knife, p is proportional to 1/area, so pressure of sharp knife is more than blunt knife.Don't get confused with the wight and pressuring, pressure is the force on a unit area that is...  morePressure= force/area, area of sharp knife is less than area of blunt knife, p is proportional to 1/area, so pressure of sharp knife is more than blunt knife.Don't get confused with the wight and pressuring, pressure is the force on a unit area that is help perpendicular whereas weight is the force by which the earth attracts everything towards it's center.  

    • June 27, 2021
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    Abdullah Masud This is simply an example of pressure in our daily lives. Here, according to Pascal's law (P = f/a, where pressure is the force applied over a certain area), the sharp knife can exert greater pressure than the blunt knife, as the sharper knife has less...  moreThis is simply an example of pressure in our daily lives. Here, according to Pascal's law (P = f/a, where pressure is the force applied over a certain area), the sharp knife can exert greater pressure than the blunt knife, as the sharper knife has less contact area for the same force than the blunt knife, so the force would be exerted over a smaller area. So in order to cut anything, one would need to apply a larger force in a blunt knife than a sharper knife, and this might result in the blunt knife cutting the hand due to excessive pressure applied by the user while cutting any other objects.  less

    • June 27, 2021
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  Taarik Hasan commented on Fatima Ahmed's classified listing.

  

  Jacob's Alaskan Trip

  Jacob's Alaskan Trip
   
  
  Jacob was a physics student at the University of Texas in Austin, Texas, USA.  His hometown was a small city called Soldotna in the Kenai Peninsula in the US state of Alaska. Soldotna's winter was extremely cold w...

  • June 9, 2021

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    Tanveer Tausif Ratul The 1st phenomena is the result of "friction" which opposes the vehicle's tyre rubber from sliding on slippery roads.The tread on the tires gripped the road surface while jacob was driving and from common sense,it can be realized that jacob's...  moreThe 1st phenomena is the result of "friction" which opposes the vehicle's tyre rubber from sliding on slippery roads.The tread on the tires gripped the road surface while jacob was driving and from common sense,it can be realized that jacob's car had winter tyres which have deeper tread.The treads grip the ice well enough & larger frictional force is produced there as the area of contact becomes larger.Treads have certain patterns that push
    away the ice and snow.So he could drive safely.If no tread, there will be less friction and driving will become unsafe.
    
    Jacob's shoes slipped because uppermost ice layer contains thin water layer on it.Deeper ice layers stick to each other well but upper layers are very loose as they always remain in contact with air.While walking, jacob's shoes rubbed on ice that caused friction.Friction created heat and heat helped to melt the ice which made it more slippery.
    Frictional force is produced where there is a kinetic force acting between the two...    less

    • June 13, 2021
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    Tanveer Tausif Ratul objects.When Jacob was rubbing his hand,a frictional force was produced which was emitted as heat.That energy didn't not come from the atmosphere, but rather the energy he was spending to overcome the frictional forces.

    • June 13, 2021
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    Abrar Ibne Amin Jim All the situations described above hints at Newton’s 3rd Law & specifically Frictional force.
    
    1) Situation-1, Jacob’s car could travel the road despite the road was slippery. This happened as the tires had enough grooves to increase friction....  moreAll the situations described above hints at Newton’s 3rd Law & specifically Frictional force.
    
    1) Situation-1, Jacob’s car could travel the road despite the road was slippery. This happened as the tires had enough grooves to increase friction. Friction increases due to rough surface, so the tires could make a firm grip on the road and prevent slipping. But if the tires hadn’t enough groove it could felt due to the smooth icy road.
    
    2) 2nd situation where Jacob slipped on the ground due to wearing regular shoes. Although static friction occurred it wasn’t enough to stop slipping as the shoes of Jacob didn’t have enough grip to increase friction.
    
    3) We can see in the 3rd situation that through rubbing his palms together, Jacob felt warm on both palms. This occurred due to sliding friction. The molecules in the palms of Jacob’s started moving quickly. Static electricity was produced due to the sliding friction. Thus this static electricity converted into heat energy. So friction is the root of this.  less

    • June 13, 2021
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    Abdullah Masud In his wonderful journey, he has met some of the interesting and fundamental laws of physics. First of all, it can be noticed that surface of the ice is slippery. So in order to prevent skidding, the tire of the car had a grooved pattern moulded into the...  moreIn his wonderful journey, he has met some of the interesting and fundamental laws of physics. First of all, it can be noticed that surface of the ice is slippery. So in order to prevent skidding, the tire of the car had a grooved pattern moulded into the rubber surface and are properly inflated which increases the amount of friction force acting on the car and so the car can move smoothly through the ice. Secondly, it is quite good to mention that normal shoes are not built to create a lot of frictional force, so as the ice is slippery, due to less frictional force, Mr Jacob slips.
    In order to prevent slipping on ice, ice boots have quite a good surface that can create a lot of friction with the ice, preventing the user of the boots from sleeping. Thirdly, rubbing hands is also an example of friction. Rubbing hands allows surfaces from both the hands to come into contact and rub against each other and this movement causes friction force to convert the kinetic energy of the hands into the thermal...    less

    • June 13, 2021
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    Shafaat Shams 1. The snowy road
    is so slippery and doesn’t have enough grips. Jacob’s Car was useful there; it
    gives power to all 4 wheels at the same time. With the help of heavy car
    weight, those 4 tires made 4 friction points. The more friction it made,...  more1. The snowy road
    is so slippery and doesn’t have enough grips. Jacob’s Car was useful there; it
    gives power to all 4 wheels at the same time. With the help of heavy car
    weight, those 4 tires made 4 friction points. The more friction it made, the
    more grip the car got. He might use frictional tires for getting more grips. In
    consequence of that, he moved easily.
    
    
    2.
    On the ice, there are
    unstable water molecules that are weakly bonded to the crystal. When Jacob
    walked on ice, the molecules began to move freely. His shoes had not enough
    friction point to grip in ice. As a result, his foot did not get enough static
    friction force to hold him in place & he slipped.
    
    
    3.
    Jacob’s hands came in contact & move relative to each
    other; the friction between the two hand surfaces converts kinetic energy into
    thermal energy. Thermal energy made his hand wormer and made it safe from being
    frozen.  less

    • June 14, 2021
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  Taarik Hasan commented on Fatima Ahmed's classified listing.

  

  Jasmine: The Pride of Sundarbans

  Jasmine: The Pride of Sundarbans
   
  
   
  I am an icon of strength, beauty, fearlessness and prowess. People know me as the Royal Bengal Tiger. My name is Jasmine and I am the pride of Sundarbans, my home!  My home, Sundarbans, is the ...

  • May 25, 2021

  • Zeba Afia and Md. Hazrat Ali like this.
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    Rawnak Jahan Khan As we know Sundarbans is the largest mangrove with rich ecosystems associated divers flora and fauna, its plays an important role to protect the southeastern part of Bangladesh. This part of Bangladesh is more exposer towards climate extremes and...  moreAs we know Sundarbans is the largest mangrove with rich ecosystems associated divers flora and fauna, its plays an important role to protect the southeastern part of Bangladesh. This part of Bangladesh is more exposer towards climate extremes and Sundarbans is the prime means of protecting the litoral community and managing Sundarbans as a healthy forest is essential thereby. Therefore when we talked about saving Sundarbans, instead of managing Sundarbans we sould be more focused on managing Sundarbans depended community. Where the best way can be alternate income generation(AIG). It could be carried out easily promoting eco-tourism in a large scale. A large number of employment can take place among Sndarbans associate community by promoting home staying, local guide, boatman etc. services. In that case, skill development to creat the circumstance tourist friendly is essential. Besides, the women should be trained to sell their native goods. This sort of intervention can be the most effective...    less

    • May 30, 2021
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    Rawnak Jahan Khan As we know Sundarbans is the largest mangrove with rich ecosystems associated divers flora and fauna, its plays an important role to protect the southeastern part of Bangladesh. This part of Bangladesh is more exposer towards climate extremes and...  moreAs we know Sundarbans is the largest mangrove with rich ecosystems associated divers flora and fauna, its plays an important role to protect the southeastern part of Bangladesh. This part of Bangladesh is more exposer towards climate extremes and Sundarbans is the prime means of protecting the litoral community and managing Sundarbans as a healthy forest is essential thereby. Therefore when we talked about saving Sundarbans, instead of managing Sundarbans we sould be more focused on managing Sundarbans depended community. Where the best way can be alternate income generation(AIG). It could be carried out easily promoting eco-tourism in a large scale. A large number of employment can take place among Sndarbans associate community by promoting home staying, local guide, boatman etc. services. In that case, skill development to creat the circumstance tourist friendly is essential. Besides, the women should be trained to sell their native goods. This sort of intervention can be the most effective...    less

    • May 30, 2021
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    Farjana Zaman Appointing community leaders as forest guards or watchman will keep the community people away from exploiting resources. Second step should be creating alternative employment facilities for other community families.

    • May 30, 2021
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    Md. Hazrat Ali The Sundarbans is a cluster of the low land island in the Bay of Bengal. It was the world’s largest mangrove with an area of 10000 Km2 where 60% in Bangladesh and the rest
    in India. The local people alongside Sundarbans are completely dependent on this...  moreThe Sundarbans is a cluster of the low land island in the Bay of Bengal. It was the world’s largest mangrove with an area of 10000 Km2 where 60% in Bangladesh and the rest
    in India. The local people alongside Sundarbans are completely dependent on this forest for their livelihood. They cut trees, catching fish, collecting honey, harvesting Golpata, etc. Above some of the work they are doing illegally. The main challenge is to improve their lives without degrading the Sundarbans if we will plan sustainably. Although economic gains are important, ecological and environmental issues must be considered in long-term development plans. The Sundarbans mangroves region is a UN Educational, Scientific, and Cultural Organization World Heritage Site, a Ramsar site, and a Class 3 tiger conservation landscape of global priority. If the local people will work jointly with the tourism board, some people will get a job like; tourist guide, driver guard, etc. They can accommodate tourists as well as provide some...    less

    • May 30, 2021
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    Hymanti Sarkar Firstly, if we notice the occupations of local people, we can see most frequently practiced professions are Mouwal, Baowal, fisherman, collecting golpata, fish fry, crab etc, poaching. So, they are highly dependent on forest. And the main reasons of this...  moreFirstly, if we notice the occupations of local people, we can see most frequently practiced professions are Mouwal, Baowal, fisherman, collecting golpata, fish fry, crab etc, poaching. So, they are highly dependent on forest. And the main reasons of this dependency are the mono-cropping characteristics of their agriculture, low literacy rate, lack of awareness, lack of facilities etc.
    So, Govt. And other agencies Should focus on their education, sanitation and other facilities. As most of them are farmer and do fish farming can practice different agroforestry systems but for this, more researches should be done to ensure which crops, trees grow well in these areas because salinity is a big problem here. And obviously sustainable dams need to be built so that tidal water does not reach the locality.
    If they get their needs which they get from Sundarbans, our forest will be safe. And those projects harm Sundarbans, they should be stopped. Besides Eco-tourism can be a safe way for economic...    less

    • May 30, 2021
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  Taarik Hasan commented on Fatima Ahmed's classified listing.

  

  Rafiq's Network Effect

  Rafiq's Network Effect
   
  
  Rafiq is a student of a reputed public university in Bangladesh. He is the only educated member of his family. He lived with his family in the village until he was admitted to the university.
  As the family's financial si...

  • May 18, 2021

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    Anika Dristi Since there is a network issue in his village SIM Internet connections like modem, the pocket router, etc. do not work very well here. The best solution for him is a broadband connection.
    As Rafiq got no money, he can lend some money from his students....  moreSince there is a network issue in his village SIM Internet connections like modem, the pocket router, etc. do not work very well here. The best solution for him is a broadband connection.
    As Rafiq got no money, he can lend some money from his students. He can use that money to buy a broadband connection. Thus he can continue his classes and his tuitions as well.
    
    He can also gather more people like him who are facing the same problem and together they can buy a broadband connection and router. Which will result in solving everyone's problem.
    
    He can also get a student loan from his Univesity.  less

    • May 20, 2021
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    Khadeeza Afruz Shammee To start the tuition, Rafiq needs to solve his problem immediately with an affordable cost. In villages, the power supply is often cut off. Rather, setup for Ethernet or wireless WIFI connection is expensive, except for SIM. So, here is my idea:
    -A...  moreTo start the tuition, Rafiq needs to solve his problem immediately with an affordable cost. In villages, the power supply is often cut off. Rather, setup for Ethernet or wireless WIFI connection is expensive, except for SIM. So, here is my idea:
    -A Pocket Router and a good quality USB extension cable can solve his problem. To get network inside his home, he can place the router on the bamboo-head or as high as possible, using a USB extension cable of 10 meters or as required. The router must be covered with waterproof something like polythene.
    -GP Pocket Router supports all SIMs. The SIM which provides best network in his village, he can purchase that SIM's data package from the retailer at least at one-third lower price.
    -For the first month, the full cost including the data package, can be up to a maximum of 3500 takas. If Rafiq does not have this amount, he can request to get the tuition fees in advance as the student is known to him. Otherwise, he can borrow the money for a month from somewhere reliable.  less

    • May 20, 2021
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    Shahriar Dipto It can be done in two ways.
    1.Getting broadband connection, & connecting it to a router that will cost 2-3 thousand tk for setup and 5-800 tk monthly.
    2. If it's not possible then, second option is buying a router (which can be connected to a modem), a...  moreIt can be done in two ways.
    1.Getting broadband connection, & connecting it to a router that will cost 2-3 thousand tk for setup and 5-800 tk monthly.
    2. If it's not possible then, second option is buying a router (which can be connected to a modem), a modem and a sim. Thus he can connect the sim to the router through modem. This will cost 2-4000 for set up and 500-1000৳ monthly. This need to be placed in a tall tree or on top of a bamboo stick where the network is good. As connecting electricity at that high place will be tough, he can attach a battery based power system which will backup for minimum 3-4 hours.
    Obviously, he can share his connection to other people who need it and thus reducing the cost to bear by himself.  less

    • May 20, 2021
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    Nishat Tamanna I will suggest him to buy a sim network booster. Though this device is a bit expensive (10,000 TK), it has no additional cost for set up. It is free of all the hassle of set up. He will also be able to share the connection with a good number of...  moreI will suggest him to buy a sim network booster. Though this device is a bit expensive (10,000 TK), it has no additional cost for set up. It is free of all the hassle of set up. He will also be able to share the connection with a good number of neighbours. Also, each university is now offering it's students 'student loan' in this pandemic, so he can take a loan and go for it easily.  

    • May 20, 2021
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    Tanjina Akter The solution could be a POCKET ROUTER. He can place the router on the top of the roof or on the bamboo head. Since the pocket router can move easily and all types of SIMs are supported, he can use it anywhere.
    
    Rafiq is a University student who earns...  moreThe solution could be a POCKET ROUTER. He can place the router on the top of the roof or on the bamboo head. Since the pocket router can move easily and all types of SIMs are supported, he can use it anywhere.
    
    Rafiq is a University student who earns for himself. Because of Covid's situation, he has to move to his native village. The issues start from here. All income source has stopped.
    
    The situation is, Rafiq does not have a proper internet connection and as a result, he is not able to continue his tuition along with his own classes. Because of his poor financial condition, he must need tuition. An adequate network at the home is the major issue in this case. As he is in the village, the electricity cut-off possibility is high. So, we cannot suggest him for broadband or wifi connection. So, the solution could be a POCKET ROUTER.  less

    • May 20, 2021
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  Noorjahan Binte Farhana is now friends with Taarik Hasan.

  • May 17, 2021
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  Khadeeza Afruz Shammee is now friends with Taarik Hasan.

  • May 16, 2021
• 
  Taarik Hasan commented on Fatima Ahmed's classified listing.

  

  Mr. Ethan's Dilemma

  Mr. Ethan's Dilemma
   
  
  Mr. Ethan was a senior political leader in a village near the Dhaka District. He also used to be a professor of Dhaka University before his political career. He was highly respected in his village community as he did an...

  • May 12, 2021

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    Yeasin Arafath As an educated person Mr.Ethan can take some steps to stop spreading covid & to develop
    their village economy. He can use his political purpose in this situation also.
    
    In my point of view some ideas are pointed...  moreAs an educated person Mr.Ethan can take some steps to stop spreading covid & to develop
    their village economy. He can use his political purpose in this situation also.
    
    In my point of view some ideas are pointed below:
    
    1.During lockdown he may arrange online learning & earning programs with younger
    & educated village people.It may help their economic condition.
    
    2.He can make a team or organization with young people those who give free service during pandemic such as
    village women can work in home(hand crafts,sewing etc.) and they can help to delivering these things.
    
    3.From political background he may manage some reliefs from govt. and distribute those with his organization’s young people.
    
    4.He can make schedules for village farmers when they go to their land to cultivate & collect their vagetables and others seeds by maintaining social distance.
    
    5.He and with the help of young people they can arrange market with maintaining social
    distance in the open ground area so that village people can buy...    less

    • May 11, 2021
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    Taarik Hasan As a Mr. Ethan and a professor and a political leader, I
    will use my knowledge from both fields....  moreAs a Mr. Ethan and a professor and a political leader, I
    will use my knowledge from both fields.
    
    
    I will separate the jobs or general people's economic contributions
    into three categories: highest, the less, and the least. The main objective is
    to keep the economy after reducing the interaction of people.
    
    
    I will set the time frame for various categories. Before the
    office hours on the very morning, the markets will be available for estern
    housing (in the evening, the western people will come).
    
    
    With the office hours, the banks and other related services
    will be there. In the evening time, the least contributors will come across
    like shopping complexes and restaurants.
    
    
    At night the manufacturers and agriculture, food services, garments,
    suppliers will work.
    
    
    
    
    
    The statistics on the economic contribution I will follow to
    set them at morning, day, or night shifts, related with one another.
    
    
    
    
    
    People must not leave houses for roaming will be ensured by
    political campaigns and creating...    less

    • May 12, 2021
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    Towhidur R. To combat against covid-19 nothing beats social distancing, closing the borders, and nationwide lockdown. But to reduce the economic backlash certain steps can be taken.
    Distribution of workforce could ensure less gathering and reduction of service....  moreTo combat against covid-19 nothing beats social distancing, closing the borders, and nationwide lockdown. But to reduce the economic backlash certain steps can be taken.
    Distribution of workforce could ensure less gathering and reduction of service. Businesses will divide the workers into shifts and follow strict guidelines. They will also have to reduce the services they provide and stay open for extra hours. Garments, constructions need to divide their workforce into shifts so it doesn't hinder their work.
    Long journeys should be restricted as it increased the chances of spreading the virus. Borders need to stay closed at all costs because new strains are being discovered on a regular basis around the globe and the effects of the mutated virus could be devastating.
    Law force should be deployed to monitor unnecessary gatherings and ensure people maintaining the guidelines in public.
    The government needs to organize relief funds to ensure infected individuals don't have to go hungry or forced to go...    less

    • May 12, 2021
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    Khadeeza Afruz Shammee Although the duration and severity of Covid-19 are terrible, it is quite impossible for a country like Bangladesh, to have a long lockdown to sustain the economy. As a policymaker, I will take the following steps :
    - I will instruct the industries to...  moreAlthough the duration and severity of Covid-19 are terrible, it is quite impossible for a country like Bangladesh, to have a long lockdown to sustain the economy. As a policymaker, I will take the following steps :
    - I will instruct the industries to work by dividing the working time into double shifts. In this way, even if the cost of running the industry is a bit higher, the density in the workplace can be avoided.
    -Since the marketplaces must be kept open, a family member from each family will be provided a movement pass for shopping at most one day of the week to avoid extra crowds.
    -Adequate number of transports would be kept running on the occasion of the upcoming festival so that the passengers can maintain minimum social distance.
    -Strict surveillance will be put in place to ensure that people are maintaining proper social distance and hygiene and not leaving their house unnecessarily. Public awareness activities should be carried out to motivate the people to abide by the necessary health norms.  less

    • May 13, 2021
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    Fatima Ahmed Thank you for all your answers everybody. We will announce the winner of this quiz tomorrow.

    • May 14, 2021
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  Noshin Tasnia is now friends with Taarik Hasan.

  • May 3, 2021
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  Taarik Hasan is now friends with Fatima Ahmed.

  • May 2, 2021
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  Taarik Hasan joined the group Coolinventor Contributors

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  Taarik Hasan has just signed up. Say hello!

  • May 2, 2021