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: if the perimeter of a rectangular garden is 1800 m , its length when its breadth is 400 m is ? 
Options: a ) 500 , b ) 600 , c ) 700 , d ) 800 , e ) 900
[EX A]: a

[EX Q]: Problem: a car drives 90 miles on local roads at 30 mph , and 75 miles on the highway at 60 mph , what is the average speed of the entire trip ? 
Options: a ) 36 mph , b ) 40 mph , c ) 39 mph , d ) 42 mph , e ) 38 mph
[EX A]: c

[EX Q]: Problem: a man can row at 4 kmph in still water . if the velocity of current is 1 kmph and it takes him 1 hour to row to a place and come back , how far is the place ? 
Options: a ) 2.4 km , b ) 2.9 km , c ) 3.4 km , d ) 1.9 km , e ) 5.6 km
[EX A]:
d