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12. the amount of money in a bank account decreased by 21.5% over the last year. if the amount of money at the beginning of the year is represented by ‘n', write 3 equivalent expressions to represent the amount of money in the bank account after the decrease?

If the sales price of a dvd is $20 and the markup is 34%, what is the cost of the dvd?

The ph level of a blueberry is 3.1 what is the hydrogen-ion concentration [h+] for the blueberry