(a): Given:
There are given that the present value is $12000 and interest is 4.5% and 20 years.
Explanation;
To find future value, we need to use the future value formula;
Then,
From the formula of future value for annually:

Where,

Then,
Put the values into the above formula:
So,

Then,

Final answer:
Hence, the future value is shown in below:;
