Given the Following Values $\mu$ = 10,M = 8 $\sigma$ _M = 0

Multiple Choice

Given the following values: $\mu$ = 10,M = 8, $\sigma$ _M = 0.5,conduct a one-sample z test at a .05 level of significance.What is the decision for a two-tailed test?

A) to reject the null hypothesis
B) to retain the null hypothesis
C) There is not enough information since the sample size is not given.