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11. When his niece was born, Mr. Hernandez opened an account to help pay for her college education. The account earns 5% interest each year. Mr. Hernandez has not deposited or withdrawn any money since he opened the account. Today, seven years after the account was opened, the balance is $1,336.75. a. Write an equation you could use to calculate the balance in the account x years from now. b. What was Mr. Hernandez's initial deposit