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: in a 80 meters race a beats b by 56 m or 7 seconds . a ' s time over the course is :
Options: a ) 3 seconds , b ) 12 seconds , c ) 10 seconds , d ) 18 seconds , e ) 28 seconds
[EX A]: a

[EX Q]: Problem: the speed at which a man can row a boat in still water is 15 km / hr . if he rows downstream , where the speed of current is 3 km / hr , how many seconds will he take to cover 90 meters ?
Options: a ) 12 , b ) 16 , c ) 17 , d ) 18 , e ) 20
[EX A]: d

[EX Q]: Problem: beginning in town a , biker bob rides his bike 12 miles west , 6 miles north , 4 miles east , and then 12 miles north , to town b . how far apart are town a and town b ? ( ignore the curvature of the earth . )
Options: a ) 18.97 miles , b ) 20 miles , c ) 22 miles , d ) 23 miles , e ) 25 miles
[EX A]:
a