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: a sum of money at simple interest amounts to rs . 815 in 3 years and to rs . 865 in 4 years . the sum is : 
Options: a ) s . 665 , b ) s . 690 , c ) s . 698 , d ) s . 700 , e ) s . 720

A: a
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Q: Problem: a shopkeeper sells his goods at cost price but uses a faulty meter that weighs 800 grams . find the profit percent . 
Options: a ) 20 , b ) 15 , c ) 25 , d ) 18 , e ) 19

A: c
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Q: Problem: a baseball card decreased in value 30 % in its first year and 10 % in its second year . what was the total percent decrease of the card ' s value over the two years ? 
Options: a ) 28 % , b ) 37 % , c ) 32 % , d ) 36 % , e ) 72 %

A:
b
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