1) Since this is a compound interest investment, we can write out the following, assuming that there will not be any other investment on this during those 4 years.
2) So, we can write out the following formula:
[tex]\begin{gathered} A=P(1+\frac{r}{n})^{nt} \\ 800=P(1+\frac{0.09}{4})^{4\times4} \\ 800=P(1+\frac{0.09}{4})^{16} \\ 800=P(1.0225)^{16} \\ P=\frac{800}{(1.0225)^{16}} \\ P\approx\$560.37 \\ \end{gathered}[/tex]Thus this is the answer
