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: two trains are moving in the same direction at 72 kmph and 36 kmph . the faster train crosses a man in the slower train in 20 seconds . find the length of the faster train ? 
Options: a ) 270 , b ) 277 , c ) 200 , d ) 257 , e ) 271

Answer: c


Question: Problem: find avrg speed if a man travels at speed of 32 km / hr up and 48 km / hr dawn at an altitude of 230 m . 
Options: a ) 25.8 , b ) 26.8 , c ) 38.4 , d ) 34.4 , e ) 29.8

Answer: c


Question: Problem: it would take one machine 9 hours to complete a large production order and another machine 8 hours to complete the same order . how many hours would it take both machines , working simultaneously at their respective constant rates , to complete the order ? 
Options: a ) 72 / 17 , b ) 17 / 72 , c ) 14 / 24 , d ) 24 / 56 , e ) 34 / 56

Answer:
a