A non-governmental organization wants to choose between two regions in a state to initiate a campaign for rainwater harvesting. A researcher claims that Region A receives lesser rainfall than Region B. To test the regions, the average rainfall is calculated for 60 days in each region. The mean rainfall in Region A is 700 millimeters. Assume the population standard deviation is 60 millimeters. The mean rainfall in Region B is 725 millimeters. Assume the population standard deviation is 66 millimeters.

At α = 0.01, can the organization support the researcher’s claim?

(a) identify the claim and state H₀, and H_a,

(b) find the critical value(s) and identify the rejection region(s),

(c) find the standardized test statistic z,

(d) decide whether to reject or fail to reject the null hypothesis, and

(e) interpret the decision in the context of the original claim. Assume the samples are random and independent, and the populations are normally distributed.