Principal amount = P = $2875
Interest rate = r = 3.15% = 0.0315
Period = t = 7 years
Compunding periods = n = 2
The formula to be used is:
[tex]A=P(1+ \frac{r}{n})^{t*n} [/tex]
Using the values, we get:
[tex]A=2875(1+ \frac{0.0315}{2})^{2*7} =3578.11[/tex]
Thus, the worth of the account after 7 years of saving will be $3578.11