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: if a book is sold at 10 % profit instead of 10 % loss , it would have brought rs 14 more . find out the cost price of the book 
Options: a ) 75 , b ) 72 , c ) 60 , d ) 70 , e ) 80
d

Problem: during a sale , the price of a pair of shoes is marked down 15 % from the regular price . after the sale ends , the price goes back to the original price . what is the percent of increase to the nearest percent from the sale price back to the regular price for the shoes ? 
Options: a ) 9 % , b ) 10 % , c ) 11 % , d ) 18 % , e ) 90 %
d

Problem: the annual interest rate earned by an investment increased by 8 percent from last year to this year . if the annual interest rate earned by the investment this year was 27 percent , what was the annual interest rate last year ? 
Options: a ) 22 % , b ) 20 % , c ) 25 % , d ) 23 % , e ) 21 %

c