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: how long does a train 165 meters long running at the rate of 54 kmph take to cross a bridge 660 meters in length ? 
Options: a ) 55 sec , b ) 40 sec , c ) 45 sec , d ) 30 sec , e ) 35 sec

A: a
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Q: Problem: a train 200 m long is running with a speed of 68 kmph . in what time will it pass a man who is running at 8 kmph in the same direction in which the train is going ? 
Options: a ) 6 sec . , b ) 7 sec . , c ) 9 sec . , d ) 12 sec . , e ) none

A: d
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Q: Problem: a and b can do a piece of work in 18 and 9 days respectively . a does the work for a few days and left , then b continued for 6 days . how many days did a and b work together ? 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5

A:
b
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