Use the Confidence Level and Sample Data to Find a Confidence

Multiple Choice

Use the confidence level and sample data to find a confidence interval for estimating the population µ. Round your answer to the same number of decimal places as the sample mean.
-A random sample of 104 light bulbs had a mean life of $\bar { x } = 543$ hours with a standard deviation of $\sigma = 26$ hours. Construct a $90 \%$ confidence interval for the mean life, $\mu$ , of all light bulbs of this type.

A) $536 \mathrm { hr } < \mu < 550 \mathrm { hr }$
B) $537 \mathrm { hr } < \mu < 549 \mathrm { hr }$
C) $538 \mathrm { hr } < \mu < 548 \mathrm { hr }$
D) $539 \mathrm { hr } < \mu < 547 \mathrm { hr }$