A market researcher wants to perform a test with the intent of establishing that his company’s pump bottle of soap has a mean lifetime greater than 40 days. The sample size is 70 and the researcher...

A market researcher wants to perform a test with the intent of establishing that his company’s

pump bottle of soap has a mean lifetime greater than 40 days. The sample size is 70 and the

researcher knows that the standard deviation σ=5.6. Assume that the lifetimes of pump

bottles of soap follow a normal distribution.



a. If you set the rejection region to be R: ?̅ ≥41.31, what is the level of significance of

your test?