In Developing an Interval Estimate for a Population Mean,the Population $\text { ? }$

Multiple Choice

In developing an interval estimate for a population mean,the population standard deviation $\text { ? }$
was assumed to be 10.The interval estimate was 50.92 $\pm$ 2.14.Had $\text { ? }$
equaled 20,the interval estimate would be:

A) 60.92 $\pm$ 2.14.
B) 50.92 $\pm$ 12.14.
C) 101.84 $\pm$ 4.28.
D) 50.92 $\pm$ 4.28.