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'.

Problem: two pipes a and b can separately fill a tank in 12 and 20 minutes respectively . a third pipe c can drain off 45 liters of water per minute . if all the pipes are opened , the tank can be filled in 15 minutes . what is the capacity of the tank ? 
Options: a ) 542 , b ) 540 , c ) 675 , d ) 829 , e ) 279
c

Problem: how many shots of 1 cm radius can be prepared from a sphere of 4 cm radius ? 
Options: a ) 33 , b ) 88 , c ) 27 , d ) 64 , e ) 99
d

Problem: ron cycles his way up on a hill side and back . he takes the exact same route both ways . on the trip out he cycles an average speed of 5 miles per hour . on the trip back , downhill cycling at an average speed of 100 miles per hour , he is quick to return back . what is his approximate average speed for the round trip in miles per hour ? 
Options: a ) 8 , b ) 9.52 , c ) 10 , d ) 11.7 , e ) 20

b