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 difference between simple and compound interest on rs . 1600 for one year at 10 % per annum reckoned half - yearly is ? 
Options: a ) 8 , b ) 3 , c ) 9 , d ) 4 , e ) 2

A: d
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Q: Problem: uncle bruce is baking chocolate chip cookies . he has 36 ounces of dough ( with no chocolate ) and 12 ounces of chocolate . how many ounces of chocolate are left over if he uses all the dough but only wants the cookies to consist of 20 % chocolate ? 
Options: a ) 3 , b ) 6 , c ) 7.2 , d ) 7.8 , e ) 9

A: a
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Q: Problem: a person lent a certain sum of money at 6 % per annum at simple interest and in 8 years the interest amounted to $ 520 less than the sum lent . what was the sum lent ? 
Options: a ) 800 , b ) 1000 , c ) 1200 , d ) 1400 , e ) 1600

A:
b
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