In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: at the end of the month , a certain ocean desalination plant ’ s reservoir contained 14 million gallons of water . this amount is twice the normal level . if this amount represents 70 % of the reservoir ’ s total capacity , how many million gallons short of total capacity is the normal level ? 
Options: a ) 2 , b ) 5 , c ) 10 , d ) 12 , e ) 15

A: c
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Q: Problem: a house wife saved $ 2.50 in buying an item on sale . if she spent $ 25 for the item , approximately how much percent she saved in the transaction ? 
Options: a ) 8 % , b ) 9 % , c ) 10 % , d ) 11 % , e ) 12 %

A: b
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Q: Problem: sabrina is contemplating a job switch . she is thinking of leaving her job paying $ 90000 per year to accept a sales job paying $ 45000 per year plus 15 percent commission for each sale made . if each of her sales is for $ 1500 , what is the least number of sales she must make per year if she is not to lose money because of the job change ? 
Options: a ) 57 , b ) 177 , c ) 178 , d ) 377 , e ) 200

A:
e
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