The continuous compound rate of decay of carbon-14 per year is r = -0.000 123 8. How

Question:

The continuous compound rate of decay of carbon-14 per year is r = -0.000 123 8. How long will it take a certain amount of carbon-14 to decay to half the original amount? Use the radioactive decay model in Problem 33.
Radioactive decay model
Q = Q0ert
where
Q0 = amount of the substance at time t = 0
r = continuous compound rate of decay
t = time in years
Q = amount of the substance at time t