Answer:
no
Explanation:
Let f represent the fraction of C-14 remaining as a function of the time t in years. Since the half-life of C-14 is about 5570 years, we have ...
f = (1/2)^(t/5570)
Taking the log and solving for t, we get ...
log(f) = (t/5570)log(1/2)
5570·log(f)/log(1/2) = t
Filling in the given value for f, the value of t we get is ...
5570·log(0.65)/log(0.5) = t ≈ 3462
It appears the estimate of 4000 years is a bit high.