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: you hold some gold in a vault as an investment . over the past year the price of gold increases by 60 % . in order to keep your gold in the vault , you must pay 10 % of the total value of the gold per year . what percentage has the value of your holdings changed by over the past year . 
Options: a ) 45 % , b ) 46 % , c ) 50 % , d ) 55 % , e ) 44 %
e

Problem: mary works in a restaurant a maximum of 70 hours . for the first 20 hours , she is paid $ 8 per hour . for each overtime hour , she is paid at a rate which is 25 % higher than her regular rate . how much mary can earn in a week ? 
Options: a ) 600 , b ) 620 , c ) 660 , d ) 320 , e ) 400
c

Problem: the cost of an article is decreased by 10 % . if the original cost is $ 100 , find the decrease cost . 
Options: a ) 33 , b ) 11 , c ) 68 , d ) 36 , e ) 90

e