You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model A and Model B are equal. You research the repair costs. The mean repair cost of 22 Model A washing machines is $210. Assume the population standard deviation is $15. The mean repair cost of 30 Model B washing machines is $226. Assume the population standard deviation is $22. At a = 0.01, can you reject the salesperson's claim? Assume the samples are random and independent, and the populations are normally distributed. Complete parts (a) through (e). (a) Identify the claim and state Ho and Ha. What is the claim? O A. The mean repair cost for Model A is greater than Model B. O B. The mean repair cost for Model A is less than Model B. O C. The mean repair costs for Model A and Model B are different. O D. The mean repair costs for Model A and Model B are equal. Let uy be the mean repair cost for Model A and let u2 be the mean repair cost for Model B. What are Ho and Ha? OA. HO: H1 SH2 OB. HO: H1 Z H2 OC. HO: H1

H2 Ha: H1

H2 OF. HO: H1 = H2 Ha: H1 = H2 Ha: H1 S H2 Ha: My # H2 (b) Find the critical value(s) and identify the rejection region(s). The critical value(s) is/are. Round to two decimal places as needed. Use a comma to separate answers as needed.) What is/are the rejection region(s)? Select the correct choice below and fill in the answer box(es) within your choice. Round to two decimal places as needed.) OA. Z OB. Z (c) Find the standardized test statistic z for 1 - H2. z= (Round to two decimal places as needed.) d) Decide whether to reject or fail to reject the null hypothesis. Choose the correct answer below. O A. Fail to reject Ho . The standardized test statistic is not in a rejection region. O B. Reject Ho. The standardized test statistic is in a rejection region. O C. Reject Ho . The standardized test statistic is not in a rejection region. O D. Fail to reject Ho . The standardized test statistic is in a rejection region. (e) Interpret the decision in the context of the original claim. At the % significance level, there is evidence to |the claim that the mean repair costs for Model A are the mean repair costs for Model B