Explanation:
To solve this problem, we need to first determine the half-life of carbon-14. Using the given decay model, we can see that the rate of decay, or the decay constant, is 0.0001211. The half-life, t1/2, is therefore ln(2)/0.0001211 = 5,730 years. We can then solve for the age of the paintings using the formula t = ln(2) / ln(A/A0). In this case, A/A0 = 0.38. So, t = ln(2)