Your friend is investing in a $401(k)$ that promises $3\%$ annual growth. He plans on investing $$750$ each month for $20$ years.

a$)$ What could you type into Excel to calculate the balance in the account after $20$ years?

$2$ points

b$)$ If the function from part a is entered correctly, Excel returns a value of $$246,226\mathrm{.}50$ for the balance in the $401(k)$ after $20$ years. How much interest is earned in the account after $20$ years? $3$ points