How long will it take $10,000 to reach $50,000 if it earns 10% annual interest compounded semiannually?

Answer: 16.5 years

Please show steps to solving this, using the below Equation. I don't know what to put in for "e"

Equation 8-7. Future Value with Continuous Compounding:

=

Where: FV = Future Value PV = Present Value e = Natural antilog of 1 n = Number of years k = Stated annual interest rate (expressed as decimal)