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: sarah operated her lemonade stand monday through friday over a two week period and made a total profit of 210 dollars . on hot days she sold cups of lemonade for a price that was 25 percent higher than the regular days . each cup she sold had a total cost of 75 cents and sarah did not incur any other costs . if every day she sold exactly 32 cups and 3 of the days were hot , then what was the price of 1 cup on a hot day ? 
Options: a ) $ 1.50 , b ) $ 1.64 , c ) $ 2.25 , d ) $ 2.50 , e ) $ 3.25

A: b
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Q: Problem: find the compound interest on $ 800 for 1 year at 10 % p . a . if ci is component yearly ? 
Options: a ) $ 40 , b ) $ 400 , c ) $ 840 , d ) $ 800 , e ) $ 80

A: a
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Q: Problem: 6 % of customers that enter a store on any given day must not pay tax . if 1000 people shop every day , how many people pay taxes in the store every week 
Options: a ) 6500 , b ) 6580 , c ) 7200 , d ) 7120 , e ) 6800

A:
b
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