You want to invest an amount today that will last 7 years and allow you to withdraw $525 at the end of each 6-month period. you earn 4% APR compounded semiannually on your investment. how much do you need to invest today to achieve your goal?

You have already saved $6900 to buy a used car. You invest this money in a certificate of deposit earning 0.25% APR compound monthly. How many years will it take your account to reach your target of $7125 in order to buy a new car?