In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: the cost price of an article is 70 % of the marked price . calculate the gain percent after allowing a discount of 10 % . 
Options: a ) 13.6 % , b ) 28.6 % , c ) 35.6 % , d ) 42.3 % , e ) none

A: b
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Q: Problem: there is 60 lit of milk and water in which milk forms 84 % . howmuch water must be added to this solution to make it solution in which milk forms 64 % 
Options: a ) 18.75 , b ) 19.75 , c ) 20.75 , d ) 21.75 , e ) 22.75

A: a
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Q: Problem: one night 10 percent of the female officers on a police force were on duty . if 200 officers were on duty that night and half of these were female officers , how many female officers were on the police force ? 
Options: a ) 90 , b ) 180 , c ) 270 , d ) 500 , e ) 1,000

A:
e
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