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'.
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Question: Problem: 28 machines can do a work in 10 days . how many machines are needed to complete the work in 40 days ? 
Options: a ) 10 , b ) 6 , c ) 4 , d ) 7 , e ) 5

Answer: d


Question: Problem: a train running at a speed of 60 kmph crosses a pole in 18 seconds . what is the length of the train ? 
Options: a ) 120 m , b ) 300 m , c ) 190 m , d ) 150 m , e ) 160 m

Answer: b


Question: Problem: a and b together can complete work in 6 days . a alone starts working and leaves it after working for 3 days completing only half of the work . in how many days it can be completed if the remaining job is undertaken by b ? 
Options: a ) 3 , b ) 8 , c ) 5 , d ) 6 , e ) 7

Answer:
a