Hello i am having trouble in america with finance . Can someone help me please!

8. Your mom is thinking of retiring. Her retirement plan will pay her either $250,000 immediately on retirement or $350,000 five years after the date of her retirement. Which alternative should she choose if the interest rate is a) 0% per year? b) 8% per year? c) 20% per year? 9. You are planning to invest $5000 in an account earning 9% per year for retirement. a. If you put the $5000 in an account at age 23, and withdraw it 42 years later, how much will you have? b. If you wait 10 years before making the deposit, so that it stays in the account for only 32 years, how much will you have at the end