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: a shopkeeper sold 50 articles at the cost price of 60 articles . then find the profit % or lost % 
Options: a ) 20 % , b ) 22 % , c ) 25 % , d ) 30 % , e ) 35 %
a

Problem: by selling an article for $ 110 , a person gains $ 10 . what is the gain % ? 
Options: a ) 25 % , b ) 30 % , c ) 50 % , d ) 20 % , e ) 10 %
e

Problem: if $ 5,000 is invested in an account that earns 4 % interest compounded semi - annually , then the interest earned after one year would be how much greater than if the $ 5,000 had been invested at 8 % simple yearly interest ? 
Options: a ) $ 4 , b ) $ 8 , c ) $ 12 , d ) $ 16 , e ) $ 432

a