6. You have just made your first $5,000 contribution to your retirement account. Assuming that you earn a 10% compound annual rate of return, and assuming that you make no more contributions, what will your account be worth when you retire in 50 years? What will it be worth when you retire if you wait 10 years to make the same single initial contribution, which will earn the same 10% compound annual rate of return (but for only 40 years)?