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: the speed of a boat in still water is 15 km / hr and the rate of current is 3 km / hr . the distance travelled downstream in 12 minutes is 
Options: a ) 1.2 km , b ) 1.8 km , c ) 2.4 km , d ) 3.6 km , e ) 1.6 km

A: d
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Q: Problem: some persons can do a piece of work in 8 days . two times the number of these people will do half of that work in ? 
Options: a ) 2 , b ) 4 , c ) 5 , d ) 6 , e ) 8

A: a
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Q: Problem: each of the three people individually can complete a certain job in 4 , 5 , and 8 hours , respectively . what is the lowest fraction of the job that can be done in 1 hour by 2 of the people working together at their respective rates ? 
Options: a ) 9 / 20 , b ) 11 / 20 , c ) 11 / 32 , d ) 13 / 40 , e ) 17 / 40

A:
d
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