Using the Rule of 72, determine 1. Tanner has invested $500 for college. What rate of return must Tanner earn for his investment to double in six years? 2. Jerrod owes $2,000 on a credit card that charges him an annual percentage rate of 18%. If Jerrod stopped making payments, how long would it be before the balance on his card reached $4,000? 3. Because Jerrod missed a payment, the credit card company automatically raised the interest rate to 24%. How many years would it be until his balance doubles, assuming he continues to make no payments? 4. If you invest $250 at 16% interest, how much will you have after 18 years