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If a population grows exponentially as dN/dt = 0.1 N (with t in years), the DOUBLING TIME is:
A$10$ years
B$\ln 2 / 0.1 \approx 6.93$ years
C$0.1 / \ln 2 \approx 0.144$ years
D$2 / 0.1 = 20$ years
Answer & Solution
Correct answer: B. $\ln 2 / 0.1 \approx 6.93$ years
Exponential growth: N(t) = N_0 e^(kt). Doubling: 2 = e^(kt) → t = ln(2)/k = ln(2)/0.1 ≈ 6.93 years.
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