Please answer completely, I keep getting different answers.

Calculate the payments based on financing the balance using the interest rates that are $1\%,2\%,$and $3\%$higher than the original rates which are all listed below.

$-$AMOUNT TO BE FINANCED FOR VEHICLE$-$$$53,621$

$-$PAYMENT FREQUENCY$-$MONTHLY

$48$ Months

$7\mathrm{.}75\%$

$8\mathrm{.}75\%$

$9\mathrm{.}75\%$

$10\mathrm{.}75\%$

$60$ Months

$7\mathrm{.}85\%$

$8\mathrm{.}85\%$

$9\mathrm{.}85\%$

$10\mathrm{.}85\%$

$72$ Months

$8\mathrm{.}35\%$

$9\mathrm{.}35\%$

$10\mathrm{.}35\%$

$11\mathrm{.}35\%$

$**$There should be $12$ caluculated answers for these$^$

Calculate total interest paid. Answer the following questions.

Hint: Total int. paid $=($monthly payment$)($number of payments$)$Amount borrowed

How much total additional interest over the life of the loan will the person who finances the vehicle for $72$ months pay versus the person who finances the vehicle for $48$months$?$

How much total additional interest over the life of the $48$ month loan must a person pay who has weaker credit and is required to pay the $+3\%$rate versus a person who receives the lowest current interest rate?