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: in how many years will a sum of money doubles itself at 12 % per annum on simple interest ? 
Options: a ) 15 % , b ) 20 % , c ) 10 % , d ) 8 % , e ) 22 %

A: d
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Q: Problem: a green lizard can travel from the green cave to the blue cave in 108 minutes ; the blue lizard can travel from the blue cave to the green cave in 25 % less time . if the green lizard started to travel 7.5 minutes before the blue lizard , how many minutes after the blue lizard , will the green lizard pass the middle line ? 
Options: a ) 2 . , b ) 3.5 . , c ) 4 . , d ) 5.5 . , e ) 6 .

A: e
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Q: Problem: a sum was put at simple interest at a certain rate for 10 years . had it been put at 5 % higher rate , it would have fetched rs . 200 more . what was the sum ? 
Options: a ) s . 550 , b ) s . 1000 , c ) s . 600 , d ) s . 200 , e ) s . 400

A:
e
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