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 rs 160 will produce the same interest at 8 % as rs . 500 produce in 4 years at 8 % 
Options: a ) 13 , b ) 13.5 , c ) 11.5 , d ) 12.5 , e ) 12

A: d
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Q: Problem: find the compound interest on $ 20000 in 2 years at 4 % per annum , the interest being compounded half - yearly ? 
Options: a ) $ 645.56 , b ) $ 1648.64 , c ) $ 954.26 , d ) $ 745.69 , e ) $ 1020.45

A: b
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Q: Problem: a merchant has 1000 kg of sugar part of which he sells at 8 % profit and the rest at 18 % profit . he gains 14 % on the whole . the quantity sold at 18 % profit is ? 
Options: a ) 700 kg , b ) 500 kg , c ) 600 kg , d ) 800 kg , e ) 900 kg

A:
c
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