REQUESTED ASSISTANCE - Would you please review the provided answer as well as the provided detailed explanation / analysis for the answer to the below fill-in the blank question. Is the provided answer correct, and what improvements can be made to expand upon the provided detailed explanation / analysis for the answer (please provide substantive responses)?

When the sample size is large (greater than 30) you can safely use a -------- test instead of a --------- test.

ANSWER: You can safely use a z test instead of a t test.

REASON: For large size of sample we can assume normal probability distribution and therefore we can use z-test, but for the small size of sample, we need to use t-test. Therefore as the size of sample is large we can always use z-test.