Please check if my answer is correct from $1-8$

What are the total interest payments $($round to the nearest $$)?$

$=$ $ $305736$

$7.$ After $15$ payments have been made, what percentage of the total interest has been paid $($round to the nearest percentage point$)?$

$=53\%$

$8.$ After $15$ payments have been made, what percentage of the total principal has been paid $($round to the nearest percentage point$)?$

$=23\%$