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: during a sale , the price of a pair of shoes is marked down 15 % from the regular price . after the sale ends , the price goes back to the original price . what is the percent of increase to the nearest percent from the sale price back to the regular price for the shoes ? 
Options: a ) 9 % , b ) 10 % , c ) 11 % , d ) 18 % , e ) 90 %

A: d
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Q: Problem: a sum was put at simple interest at a certain rate for 3 years . had it been put at 2 % higher rate , it would have fetched rs . 360 more . find the sum . 
Options: a ) 3000 , b ) 6000 , c ) 2000 , d ) 4000 , e ) none of them

A: b
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Q: Problem: the ratio of investments of two partners p and q is 7 : 5.00001 and the ratio of their profits is 7.00001 : 10 . if p invested the money for 5 months , find for how much time did q invest the money ? 
Options: a ) 28 , b ) 10 , c ) 288 , d ) 277 , e ) 211

A:
b
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