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 250 m long running at 72 kmph crosses a platform in 15 sec . what is the length of the platform ? 
Options: a ) 50 m , b ) 200 m , c ) 250 m , d ) 270 m , e ) 300 m

Answer: a


Question: Problem: in one hour , a boat goes 21 km / hr along the stream and 11 km / hr against the stream . the speed of the boat in still water ( in km / hr ) is : 
Options: a ) 12 kmph , b ) 13 kmph , c ) 14 kmph , d ) 15 kmph , e ) 16 kmph

Answer:
e