please help me ..my teacher give hard question

MoonTrust is a Personal Financial Center that offers high quality financial services to the people who need immediate financial aids. Amidst to the Covid-19 pandemic, the company is introducing a debt consolidation loan that help people to simplify multiple debts into a single facility at affordable rates. The debt consolidation loan payment is based on "15% APR amortized over a 5-year term". This mean the loan is amortized at 15% with fixed monthly payment. Therefore, it is expected to save the total of the monthly payments on several hypothetical loans/debts by RM592.72 per month. (See the following table) (a). Using the interest rate and monthly payment for the 5 years, how much money will still be owed at the end of the 3 years? (b). How much is paid at the end of 5th years? (c). How much would the total principal paid, and total interest paid at the end of the loan repayment period if the loan is to be shorten to 4 years? (d). How long and how much would it take to pay off the debts under the original debt financing plan if interest were 21% on each loan? Original Debt Financing Plan Debt Consolidation Loan Outstanding Loan Amount Monthly Monthly [RM) Payment (RM) Loan Amount Loan/Debt Type (RM) Payment (RM) Credit Cards 25,000 941.88 Paid off None Auto Loan 50.000 1226 8 Paid off None Unsecured Debt 15.000 565.13 Paid off None Debt Consolidation 90.000 Loan 2,141 09 Total 90.000 2733.81 90 000 2.141.09