Answer:
40.1 < μ < 43.3
Step-by-step explanation:
Margin of error = critical value × standard error
ME = CV × SE
At 99% confidence and 38 degrees of freedom, CV = 2.712.
SE = s / √n
SE = 3.86 / √39
SE = 0.618
So the margin of error is:
ME = 2.712 × 0.618
ME = 1.7
So the 99% confidence interval of the population mean is:
μ = 41.7 ± 1.7
40.0 < μ < 43.4
Closest answer is the first one.