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 can row upstream at 5 kmph and downstream at 25 kmph , and then find the speed of the man in still water ? 
Options: a ) 15 , b ) 77 , c ) 30 , d ) 88 , e ) 34
[EX A]: a

[EX Q]: Problem: the radius of the wheel of a bus is 70 cms and the speed of the bus is 66 km / h , then the r . p . m . ( revolutions per minutes ) of the wheel is 
Options: a ) 200 , b ) 250 , c ) 300 , d ) 330 , e ) none of these
[EX A]: b

[EX Q]: Problem: sarah is driving to the airport . after driving at 25 miles per hour for one hour , she realizes that if she continues at that same average rate she will be an hour late for her flight . she then travels 50 miles per hour for the rest of the trip , and arrives 30 minutes before her flight departs . how many miles did she drive in all ? 
Options: a ) 100 , b ) 175 , c ) 210 , d ) 245 , e ) 280
[EX A]:
a