If $5000 is invested at 13.5%, compounded continuously, then the future value S at any time t

Question:

If $5000 is invested at 13.5%, compounded continuously, then the S at any time t (in years) is given by S = 5000e0.135t.
(a) What is the amount after 9 months?
(b) How long will it be before the investment doubles?
Future Value
Future value (FV) is the value of a current asset at a future date based on an assumed rate of growth. The future value (FV) is important to investors and financial planners as they use it to estimate how much an investment made today will be worth...