In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

[Q]: Problem: a and b together can do a work in 4 days . if a alone can do it in 20 days . in how many days can b alone do it ?
Options: a ) 11 , b ) 5 , c ) 6 , d ) 8 , e ) 25
[A]: b

[Q]: Problem: a 70 cm long wire is to be cut into two pieces so that one piece will be 2 / 3 th of the other , how many centimeters will the shorter piece be ?
Options: a ) 35 , b ) 20 , c ) 28 , d ) 36 , e ) 30
[A]: c

[Q]: Problem: jane makes toy bears . when she works with an assistant , she makes 80 percent more bears per week and works 10 percent fewer hours each week . having an assistant increases jane ' s output of toy bears per hour by what percent ?
Options: a ) 20 % , b ) 80 % , c ) 100 % , d ) 180 % , e ) 200 %
[A]:
c