with formula plz

. Suppose you plan to put away some years to build up a nest egg to use as a down payment on a house. You start off by putting away $2,000 today, and over the next three years you are able to put away $3,000 at the end of the first year, $4,000 at the end of the second year, and $5,000 at the end of the third year. How much will you have saved by the end of the third year if your investment rate is 5% per year