What is the half-life of a radioactive substance with a decay constant of 0.10 per year?
Correct: C
To calculate the half-life of the radioactive substance, we can use the formula t1/2 = ln(2) / λ, where λ is the decay constant. Plugging in the value of λ, we get t1/2 = ln(2) / 0.10 = 6.93 years, which is closest to 7.0 years among the given choices.