REQUESTED ASSISTANCE - Would you please review the provided answer as well as the provided detailed explanation / analysis for the answer to the below hypothesis testing question. Is the provided answer correct, and what improvements can be made to the provided detailed explanation / analysis for the answer?

If the alternative hypothesis is "MU < 5" what type of test need to be conducted?

ANSWER: MU is a letter used to show mean of the population and the test for mean is t-test or z-test. If the size of sample is small we should conduct lower tail t-test and if the size of sample is large we should conduct z-test. As the alternative hypothesis is indicating MU< 5 that is indicating rejection region on lower tail, the test is lower tail t-test or lower tail z-test depending on the size of sample.