Please show me how to calculate rate.

You saving up to buy a car that will cost $26,493 in four years at time 4. you plan on making first savings deposit one year from today, and then making an additional deposit in each of the following 3 years. These are the amounts you plan to save at the end of each year:

Year	Project Savings Amount
1	$4,000
2.	$5,000
3.	$7,000
4	$9,000

What rate will you need to earn to have enough in your savings account four years from now when you will but the car? (Show your work)