Suppose you borrow $$21,000$ from your bank to buy a car. You agree to pay $$433\mathrm{.}89$ per month for $60$ months. What is the interest rate $($APR$)$ for the loan?

$5\mathrm{.}8\%$

$6\mathrm{.}4\%$

$7\%$

$7\mathrm{.}6\%$

$8\mathrm{.}2\%$

$8\mathrm{.}8\%$