Please give me some hints to do questions 6,7,8. Thank you!!!

Number of years you have to repay the loan, n. Number of quarters you have to repay the loan, n*m Nominal interest rate p.a compounded quarterly (jm) Effective quarterly interest rate (i-jm/m) Original loan amount Fixed quaterly repayment (P&I) amount 36 144 9.00% 2.25% $935,264 $21,933.87 Q6 Q7 Q8 New Scenario (Independent): Suppose you only repay the interest amount of the loan each quarter end for the first 19 quarters. To be able to pay off the loan by the original date, you will need to repay higher equal quarter- end repayments when the interest-only period expires. Calculate the principal paid in the quarter 38 of the whole loan term. New Scenario (Independent): Right after you have repaid 36 times, the interest rate increases. To pay off the loan by the original date, you need to increase the original quarter-end repayment amount by $700. Calculate the increased nominal interest rate p.a. compounded quarterly. New Scenario (Independent): You lose your job because of COVID-19 and the bank agrees that you do not make any repayment from the begining of the loan term until the end of quarter 41. The interest keeps accumulating during this period. From quarter 42, you will need to repay higher equal quarter- end repayments to pay off the loan by the original date. Calculate the increased quarter-end repayment amount. 0.0233