When the following hypotheses are being tested at a level of significance of


aH0: m 100
Ha: m < 100

the null hypothesis will be rejected if the test statistic Z is

a. >Z
b. >Z
c. <Z
d. <100

You are lacking information on variability and level of significance used (e.g., P ≤ .05, P ≤ .01).

It would also help if you proofread your questions before you posted them. Choices a and b are identical.

To determine if the null hypothesis should be rejected or not, we need to compare the test statistic, Z, with a critical value.

In this case, since the alternative hypothesis (Ha) states that the population mean (m) is less than 100, we are conducting a left-tailed test.

The critical value for a left-tailed test is found in the left tail of the standard normal distribution (Z-distribution). The critical value represents the point at which we can reject the null hypothesis.

Since the question does not provide a specific critical value, we assume that Z is the test statistic and represents the standard normal distribution.

Therefore, the null hypothesis will be rejected if the test statistic Z is LESS THAN the critical value.

So, the correct answer is c. <Z