Find out the critical region and critical values for z that would be employed to test the null hypothesis at the given level of significance, as stated in each of the following:
(A) Ho:µ ? 45 and Ha: µ >45 , a = 0.10
(B) Ho: µ = 25 and Ha: µ ? 25 , a = 0.01
(C) Ho: µ ? 57 and Ha: µ < 57 , a = 0.05