would really appreciate help on this questions im stuck on thank you! hopefully me typing the questions out is better than the picture before thank you!

Shirley, a recent college graduate, excitedly described to her older sister the$1,560 sofa, table, and chairs she found today. However, when asked she could not tell her sister which interest calculation method was to be used on her credit-based purchase. Calculate the monthly payments and total cost for a bank loan assuming a one-year repayment period and13.25 percent interest. Now, assume the store uses the add-on method of interest calculation. Calculate the monthly payment and total cost with a one-year repayment period and11.25 percent interest. Using the information above, how much interest will Shirley "save" or be rebated if she can repay the loans after six months?