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 600 meter long train crosses a signal post in 15 seconds . how long will it take to cross a 3 kilometer long bridge , at the same speed ? 
Options: a ) 4 min , b ) 2 min , c ) 8 min , d ) 9 min , e ) 1.5 min

A: e
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Q: Problem: a and b go around a circular track of length 400 m on a cycle at speeds of 36 kmph and 36 kmph . after how much time will they meet for the first time at the starting point ? 
Options: a ) 40 sec , b ) 198 sec , c ) 178 sec , d ) 665 sec , e ) 276 sec

A: a
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Q: Problem: a and b can do a piece of work in 60 days and 60 days respectively . they work together for 10 days and b leaves . in how many days the whole work is completed ? 
Options: a ) 30 days , b ) 35 days , c ) 40 days , d ) 45 days , e ) 50 days

A:
a
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