A Group of 59 Randomly Selected Students Have a Mean $\mu _ { e }$

Multiple Choice

A group of 59 randomly selected students have a mean score of 29.5 with a standard deviation of 5.2 on a placement test. What is the 90% confidence interval for the mean score, $\mu _ { e }$ , of all students taking the test?

A) $27.9 < \mu < 31.1$
B) $28.4 < \mu < 30.6$
C) $28.2 < \mu < 30.8$
D) $27.8 < \mu < 31.2$