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: an error 6 % in excess is made while measuring the side of a square . the percentage of error in the calculated area of the square is : 
Options: a ) 12.36 , b ) 8.36 , c ) 9.36 , d ) 10.36 , e ) 11.36
a

Problem: a milk man has 15 liters of milk . if he mixes 5 liters of water , which is freely available , in 20 liters of pure milk . if the cost of pure milk is rs . 18 per liter , then the profit of the milkman , when he sells all the mixture at cost price is : 
Options: a ) 20 % , b ) 25 % , c ) 33.33 % , d ) 18 % , e ) none of these
a

Problem: a merchant marks goods up by 75 % and then offers a discount on the marked price . the profit that the merchant makes after offering the discount is 5 % . what % discount did the merchant offer ? 
Options: a ) 20 % , b ) 25 % , c ) 35 % , d ) 40 % , e ) 45 %

d