Posted by **Melanie** on Wednesday, November 14, 2012 at 7:35am.

When estimating a population mean μ, where the population standard deviation σ is known, we can:

a. choose a larger z value, construct a wider confidence interval, and achieve a lower confidence level

b. choose a smaller z value, construct a narrower confidence interval, and achieve a higher confidence level

c. define the limits of an interval estimate of μ as x ± zα/2σ/√n

d. define the limits of an interval estimate of μ as x ± tα/2·5/n