$($a$)$ Compute the amount a borrower must repay per month, given a mortgage loan having principal $250,000,$ a fixed monthly interest rate of $0\mathrm{.}5\%$ and a term of $35$ years.

$($b$)$ Consider a mortgage having the same principal and rate of interest as above, but this time the monthly repayment is $1300.$ What is the term of the loan?

$($c$)$ Suppose that the borrower wishes to borrow the same amount as above, at the same rate of interest, but can only afford to repay $1200$ per month What is going to happen in this situation?

Do parts$($a$)($b$)$ and $($c$)$ please $!!!$