Erin and Scott have just taken out a mortgage loan for $$168,308.$ The interest rate is $7\mathrm{.}13\%$ and the term is $30$ years. Calculate their monthly payment for this loan. If they pay twice the monthly payment you calculated, how long will it take them to pay off their loan? If they pay half the monthly payment you calculated, how long will it take them to pay off this loan? answer each seprtately. Include the formulas for spreadsheets, google sheets.