You have ​$10 comma 000 to invest. one bank pays 7​% interest compounded quarterly and a second bank pays 3.9​% interest compounded monthly. complete parts​ (a) and​ (b).
a. use the formula for compound interest to write a function for the balance in each bank at any time t. write a function for the balance in the first bank at any time t. choose the correct answer below.