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'.

[EX Q]: Problem: a man sitting in a train which is travelling at 64 kmph observes that a goods train travelling in a opposite direction , takes 18 seconds to pass him . if the goods train is 420 m long , find its speed . 
Options: a ) 32 , b ) 15 , c ) 18 , d ) 20 , e ) 25
[EX A]: d

[EX 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
[EX A]: b

[EX Q]: Problem: a glucose solution contains 20 grams of glucose per 1000 cubic centimeters of solution . if 500 cubic centimeters of the solution were poured into an empty container , how many grams of glucose would be in the container ? 
Options: a ) 10.00 , b ) 15.00 , c ) 11.50 , d ) 10.50 , e ) 9.75
[EX A]:
a