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'.
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Question: Problem: john traveled 80 % of the way from yellow - town to green - fields by train at an average speed of 80 miles per hour . the rest of the way john traveled by car at an average speed of v miles per hour . if the average speed for the entire trip was 60 miles per hour , what is v in miles per hour ? 
Options: a ) 30 , b ) 40 , c ) 50 , d ) 55 , e ) 70

Answer: a


Question: Problem: a train 140 m long running at 84 kmph crosses a platform in 16 sec . what is the length of the platform ? 
Options: a ) 287 , b ) 298 , c ) 233 , d ) 726 , e ) 267

Answer: c


Question: Problem: a square has a side 5 centimeters shorter than the side of a second square . the area of the larger square is four times the area of the smaller square . find the side of each square 
Options: ['a ) 5', 'b ) 6', 'c ) 7', 'd ) 8', 'e ) 9']

Answer:
a