Determine the level of significance for a hypothesis test in each of the following populations given the

Question:

Determine the level of significance for a hypothesis test in each of the following populations given the specified standard error and critical values.
(a) μ = 100, σM = 8, critical values: 84.32 and 115.68
(b) m = 100, σM = 6, critical value: 113.98
(c) m = 100, σM = 4, critical value: 86.8