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 300 m long train crosses a platform in 45 sec while it crosses a signal pole in 18 sec . what is the length of the platform ? 
Options: a ) 287 , b ) 350 , c ) 828 , d ) 450 , e ) 122

Answer: d


Question: Problem: a constructor estimates that 3 people can paint mr khans house in 4 days . if he uses 4 people instead of 3 , how long will they take to complete the job ? 
Options: a ) 2 , b ) 8 , c ) 1 , d ) 3 , e ) 4

Answer: d


Question: Problem: a person can swim in still water at 4 km / h . if the speed of water 2 km / h , how many hours will the man take to swim back against the current for 8 km ? 
Options: a ) 4 , b ) 7 , c ) 8 , d ) 9 , e ) 6

Answer:
a