Urgent! determine the amount of time it would take $4000 to double if the interest rate is 4% compounded continuously. round your answer to the nearest tenth of a year .

The equation for future value F of principal P over t years at r% interest compounded continuously is

F=Pe^(rt) =>
8000 = 4000*e^(0.04*t)
Solve for t:
e^(0.04t)=8000/4000=2
0.04t=log(2)
t=log(2)/0.04=17.33 (years)