Use Excel to answer question below

Peter borrowed $800,000 to refit his fishing trawler.The loan requires monthly repayments over 15 years.When he borrowed the money the interest rate was 13.5% per annum, but 18 months later the bank increased the interest rate to 15% per annum, in line with market rates.The bank tells Peter he can increase his monthly repayment (so as to pay off the loan by the originally agreed date) or he can extend the term of loan (and keep making the same monthly repayment).Calculate:

a. The new monthly repayment if Peter accepts the first option.

b. The extra period added to the loan term if Peter accepts the second option.