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'.

Q: Problem: a particular library has 75 books in a special collection , all of which were in the library at the beginning of the month . these book are occasionally loaned out through an inter - library program . if , by the end of the month , 80 percent of books that were loaned out are returned and there are 67 books in the special collection at that time , how many books of the special collection were loaned out during that month ? 
Options: a ) 20 , b ) 30 , c ) 35 , d ) 40 , e ) 55

A: d
****
Q: Problem: the majority owner of a business received 25 % of the profit , with each of 4 partners receiving 25 % of the remaining profit . if the majority owner and two of the owners combined to receive $ 40,000 , how much profit did the business make ? 
Options: a ) $ 44,000 , b ) $ 54,000 , c ) $ 64,000 , d ) $ 84,000 , e ) $ 104,000

A: c
****
Q: Problem: in a certain village , 150 litres of water are required per household per month . at this rate , if there are 10 households in the village , how long ( in months ) will 6000 litres of water last ? 
Options: a ) 8 , b ) 10 , c ) 6 , d ) 2 , e ) 4

A:
e
****