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'.

[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
[A]: a

[Q]: Problem: a man started driving at a constant speed , from the site of a blast , the moment he heard the blast . he heard a second blast after a time of 30 mins and 12 seconds . if the second blast occurred exactly 30 mins after the first , how many meters was he from the site when he heard the second blast ? ( speed of sound = 330 m / s )
Options: a ) 3120 , b ) 3330 , c ) 3540 , d ) 3750 , e ) 3960
[A]: e

[Q]: Problem: steve traveled the first 2 hours of his journey at 30 mph and the last 3 hours of his journey at 80 mph . what is his average speed of travel for the entire journey ?
Options: a ) 68 mph , b ) 56.67 mph , c ) 60 mph , d ) 64 mph , e ) 66.67 mph
[A]:
c