In Developing an Interval Estimate for a Population Mean, the Population

Multiple Choice

In developing an interval estimate for a population mean, the population standard deviation  was assumed to be 10. The interval estimate was 50.92 ± 2.14. Had the population standard deviation equaled 20, the interval estimate would have been:

A) 60.92 ± 2.14.
B) 50.92 ± 12.14.
C) 101.84 ± 4.28.
D) 50.92 ± 4.28.