The figure below shows the balance, P, in a bank account. P (dollars) a = P = f(t) (5, 7000) (1, 4000) t (years) (a) Find a possible formula for P = f(t) = ab' assuming the balance grows exponentially. Round your answers to three decimal places. (b) What was the initial balance? and b = Round your answer to two decimal places. Initial Balance =$ i M. (c) What annual interest rate does the account pay? a = i (b) What was the initial balance? Round your answer to two decimal places. Initial Balance = $ i and b = The annual interest rate is i i (c) What annual interest rate does the account pay? Round your answer to three decimal places. %.