#### Explanation:

They intend that $n$ be the number incidents of calculating the interest in 1 year. So as it is only calculated once $n = 1$

They intend that $r$ be the percentage interest $r = \frac{7}{100}$
Note that $\frac{\frac{7}{100}}{n} = \frac{\frac{7}{100}}{1} = \frac{7}{100}$

They intend that $t$ be the number of years.

They intend that $A \left(t\right)$ be the sum of the principle sum (P) and any interest at time $t$

So:

A(t)=P(1+r/n)^(nt) " "->" "A(t)=$500(1+7/100)^4 A(t)=$500xx(107/100)^4

A(t)=$655.398005 A(t)=$655.40 to 2 decimal places