Your classmate tells you the details of the great deal he got on his mortgage: $30-$year $1\mathrm{.}1\%$ fixed rate with a $20\%$ down payment

If his new home costs $$136,000,$ what is his down payment?

How much is he going to borrow to buy the house $($assuming he only has the money to make the down payment from the previous part$)?$

Use Excel$$s PMT function to determine how much his monthly payments would be$.$

How much will he pay in interest over the lifetime of this mortgage?