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: a can do a piece of work in 12 days . he worked for 15 days and then b completed the remaining work in 10 days . both of them together will finish it in .
Options: a ) 12 1 / 2 days , b ) 10 1 / 2 days , c ) 12 1 / 3 days , d ) 10 1 / 3 days , e ) 11 1 / 2 days

Answer: a

Question: Problem: a train 120 m long running at 60 kmph crosses a platform in 20 sec . what is the length of the platform ?
Options: a ) 213 , b ) 298 , c ) 350 , d ) 726 , e ) 267

Answer: a

Question: Problem: a boy traveled from the village to the post - office at the rate of 12.5 kmph and walked back at the rate of 2 kmph . if the whole journey took 5 hours 48 minutes , find the distance of the post - office from the village .
Options: a ) 5 km , b ) 7 km , c ) 9 km , d ) 10 km , e ) 12 km

Answer:
d