Exhibit 8-2 A Random Sample of 121 Automobiles Traveling on an Interstate

Multiple Choice

Exhibit 8-2
A random sample of 121 automobiles traveling on an interstate showed an average speed of 65 mph. From past information, it is known that the standard deviation of the population is 22 mph.
-Refer to Exhibit 8-2. If we are interested in determining an interval estimate for μ at 96.6% confidence, the Z value to use is

A) 1.96
B) 0.483
C) 2.12
D) 1.645