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 and b together do a work in 20 days . b and c together in 15 days and c and a in 12 days . so a , b and c together finish same work in how many days ? 
Options: a ) 12 , b ) 15 , c ) 8 , d ) 10 , e ) 11

A: d
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Q: Problem: ram , who is half as efficient as krish , will take 24 days to complete a task if he worked alone . if ram and krish worked together , how long will they take to complete the task ? 
Options: a ) 16 days , b ) 12 days , c ) 8 days , d ) 6 days , e ) 18 days

A: c
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Q: Problem: a and b go around a circular track of length 600 m on a cycle at speeds of 36 kmph and 60 kmph . after how much time will they meet for the first time at the starting point ? 
Options: a ) 120 sec , b ) 176 sec , c ) 178 sec , d ) 187 sec , e ) 180 sec

A:
e
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