Test for single mean.
1. An aircraft manufacturer is attempting to establish if the average leg length of adult male has changed from 44". A sample of 81 men was selected randomly and the average length was found to be 45.5", with a standard deviation of 5.5". Test the null hypothesis that the average leg length of the adult male is 44", at a = 0.05.
2. If Z = 1.96, s = 3, and E = 1, conclude the correct sample size.
a. 150
b. 35
c. 6
d. 12