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'.

Problem: what profit percent is made by selling an article at a certain price , if by selling at 1 / 2 rd of that price , there would be a loss of 20 % ? 
Options: a ) 20 % , b ) 29 % , c ) 60 % , d ) 27 % , e ) 28 %
c

Problem: the difference between compound interest and simple interest on a certain amount of money at 5 % per annum for 2 years is 17 . find the sum : 
Options: a ) 4500 , b ) 7500 , c ) 5000 , d ) 6800 , e ) none of these
d

Problem: the ratio of investments of two partners p and q is 7 : 5 and the ratio of their profits is 7 : 10 . if p invested the money for 7 months , find for how much time did q invest the money ? 
Options: a ) 11 , b ) 10 , c ) 18 , d ) 16 , e ) 14

e