## Exercise #11 - Creating a method

The formula for compound interest is:

FV = PV(1+i)^{n}

Where
FV is the Future Value, PV is the Present Value, i is the interest rate, and n
is the number of periods.
For example, if the interest rate i is 0.05, the Present Value is $1000, and the
number of periods n is 12, then the Future Value is 1000*(1.05)^{12} which is
$1795.86.

Write a program with a method called FutureValue that takes as input PV, i, and
n. It should return FV as a double.

For example, FutureValue(1000,0.05,12) should return
1795.86.

Test your program by outputting the return value for different inputs.