Please use formula to calculate K, Thank you.

4. A loan of $250,000 is to be repaid in seven annual installments, starting one year after the loan (a) The loan is repaid in equal annual payments, and the effective annual interest rate for the (b) The first three payments are equal and the last four payments are equal. The first payment was made. Construct an amortization schedule for the loan in each of the following cases: O. is four times the last payment. The effective annual interest rate is 3% throughout the loan. Hint: The payments are 4K,4K,4K, K, K, K, K.] (c) The amount of annual payment increases by 5% every year, and the effective annual interest rate is 3%