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: an employer pays rs . 20 for each day a worker works and for felts rs . 3 for each day is ideal at the end of sixty days a worker gets rs . 280 . for how many days did the worker remain ideal ? 
Options: a ) 10 , b ) 40 , c ) 30 , d ) 20 , e ) 50

A: b
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Q: Problem: the sum of 4 consecutive even numbers is 140 . what would be the smallest number ? 
Options: a ) 32 , b ) 88 , c ) 70 , d ) 123 , e ) 12

A: a
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Q: Problem: two pipes a and b can separately fill a tank in 10 and 15 minutes respectively . a third pipe c can drain off 45 liters of water per minute . if all the pipes are opened , the tank can be filled in 15 minutes . what is the capacity of the tank ? 
Options: a ) 450 , b ) 540 , c ) 542 , d ) 829 , e ) 279

A:
a
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