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'.

Q: Problem: a can do a work in 24 days and b can do it in 8 days . in how many days a and b can do the work ? 
Options: a ) 20 days , b ) 10 days , c ) 6 days , d ) 8 days , e ) 7 days

A: c
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Q: Problem: a can do a piece of work in 18 days and b alone can do it in 10 days . b works at it for 5 days and then leaves . a alone can finish the remaining work in 
Options: a ) 5 days , b ) 6 days , c ) 7.5 days , d ) 8.5 days , e ) 9 days

A: e
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Q: Problem: how many seconds will a train 100 meters long take to cross a bridge 250 meters long if the speed of the train is 36 kmph ? 
Options: a ) 54 sec , b ) 35 sec , c ) 25 sec , d ) 45 sec , e ) 24 sec

A:
b
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