You have just purchased a home and taken out a $ $480,000$ mortgage. The mortgage has a $30-$year term with monthly payments and an APR of $4\mathrm{.}72\%.$

a$.$ How much will you pay in$$ interest, and how much will you pay in$$ principal, during the first$$ year?

b$.$ How much will you pay in$$ interest, and how much will you pay in$$ principal, during the $20$th year$($i$.$e$.,$ between $19$ and $20$ years from$$ now$)?$