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 price of a t . v . set worth rs . 15000 is to be paid in 20 installments of rs . 1500 each . if the rate of interest be 6 % per annum , and the first installment be paid at the time of purchase , then the value of the last installment covering the interest as well will be ? 
Options: a ) 29997 , b ) 28088 , c ) 13500 , d ) 19000 , e ) 2799

A: c
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Q: Problem: alex takes a loan of $ 5,000 to buy a used truck at the rate of 2 % simple interest . calculate the annual interest to be paid for the loan amount . 
Options: a ) 100 , b ) 150 , c ) 720 , d ) 200 , e ) 750

A: a
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Q: Problem: if each side of a square is increased by 325 % in length , find the percentage change in its area ? 
Options: a ) 54 % , b ) 957 % , c ) 956.25 % , d ) 958.25 % , e ) 959.50 %

A:
c
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