2.

A shareholders' group is lodging a protest against your company. The shareholders group claimed that the mean tenure for a chief exective office (CEO) was at least 9 years. A survey of 81 companies reported in The Wall Street Journal found a sample mean tenure of 7.2 years for CEOs with a standard deviation of s = 4.6 years (The Wall Street Journal, January 2, 2007). You don't know the population standard deviation but can assume it is normally distributed. You want to formulate and test a hypothesis that can be used to challenge the validity of the claim made by the group, at a significance level of a = 0.05. Your hypotheses are: Hou = 9 HA: u