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
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Q: Problem: if leo gains 10 pounds , he will weigh 50 % more than his sister kendra . currently their combined weight is 160 pounds . what is leo ' s current weight ? 
Options: a ) 80 , b ) 86 , c ) 92 , d ) 98 , e ) 104

A: c
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Q: Problem: i sold a book at a profit of 10 % . had i sold it for $ 150 more , 15 % would have been gained . find the cost price ? 
Options: a ) $ 2000 , b ) $ 2500 , c ) $ 3000 , d ) $ 3120 , e ) $ 1540

A:
c
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