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: two pipes can fill a tank in 18 minutes and 20 minutes . an outlet pipe can empty the tank in 45 minutes . if all the pipes are opened when the tank is empty , then how many minutes will it take to fill the tank ? 
Options: a ) 1 / 15 , b ) 1 / 16 , c ) 1 / 11 , d ) 1 / 10 , e ) 1 / 12
[A]: e


[Q]: Problem: stacy has a 81 page history paper due in 3 days . how many pages per day would she have to write to finish on time ? 
Options: a ) 9 , b ) 27 , c ) 10 , d ) 8.5 , e ) 6
[A]: b


[Q]: Problem: the length of a room is 5.5 m and width is 3.75 m . find the cost of paving the floor by slabs at the rate of rs . 400 per sq . metre . 
Options: a ) rs . 15000 , b ) rs . 8250 , c ) rs . 15600 , d ) rs . 16500 , e ) none of these
[A]:
b