Problem 4 15 points Suppose you deposit $3500 into an investment account that has returns of 8% annual interest for the first four years, and 6% annual interest for the next three years. a. How much is in the account at the end of the seven years? $5671.27 b. What is the single effective annual interest rate over the seven years? 7.138% c. What uniform annual deposit in years 1-7 would yield the same amount in the account at the end of year seven? $663.28