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: in a certain math department , students are required to enroll in either calculus or trigonometry , each of which is offered in beginner and advanced courses . the number of students enrolled in trigonometry is 50 % greater than the number of students enrolled in calculus , and 80 % of calculus students are enrolled in the beginner course . if 4 / 5 of students are in the beginner courses , and one student is selected at random , what is the probability that a beginner trigonometry student is selected ? 
Options: a ) 40 % , b ) 44 % , c ) 48 % , d ) 52 % , e ) 56 %

A: c
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Q: Problem: there is 60 lit of milk and water in which milk forms 84 % . howmuch water must be added to this solution to make it solution in which milk forms 64 % 
Options: a ) 18.75 , b ) 19.75 , c ) 20.75 , d ) 21.75 , e ) 22.75

A: a
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Q: Problem: the calendar of the year 2032 can be used again in the year ? 
Options: a ) 2060 , b ) 2050 , c ) 2040 , d ) 2033 , e ) 2034

A:
a
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