Please explain how to get both answers as well please

When Heather had 2 years left in college, she took out a student loan for $13,425. The loan has an annual interest rate of 8.1%. Heather graduated 2 years after acquiring the loan and began repaying the loan immediately upon graduation. According to the terms of the loan, Heather will make monthly payments for 4 years after graduation. During the 2 years she was in school not making payments, the loan accrued simple interest. Answer each part. Do not round intermediate computations, and round your answers to the nearest cent. If necessary, refer to the list of financial formulas. (a) If Heather's loan is subsidized, find her monthly payment. X ? Subsidized loan monthly payment: $ (b) If Heather's loan is unsubsidized, find her monthly payment. Unsubsidized loan monthly payment: $ Submi