$300,000$ mortgage $($zero down$-$payment$).$Maturity $15$ years $20$ years $30$ years

Spot Rate $5\mathrm{.}56\%8\%6\%1.$ What will be your monthly mortgage payment if you pick the $20-$year mortgage $($assume monthly compounding$)?$

$2.$ What will be your monthly mortgage payment if you pick the $30-$year mortgage $($assume monthly compounding$)?$