A borrower is faced with choosing between two loans. Loan A is available for $$76,000$ at $6$ percent interest for $30$ years, with $6$ points to be included in closing costs. Loan B would be made for the same amount, but for $7$ percent interest for $30$ years, with $2$ points to be included in the closing costs. Both loans will be fully amortizing.

Required:a$.$If the loan is repaid after $20$ years, what is the effective interest rate for loan A and B $?$b$.$If the loan is repaid after five years, what is the effective interest rate for loan A and B$?$