A company claims that the mean monthly residential electricity consumption in a certain region is more than 870 kiloWatt-hours (kWh). You want to test this claim. You find that a random sample of 67 residential customers has a mean monthly consumption of 900 kWh. Assume the population standard deviation is 120 kWh. At a = 0.01, can you support the claim? Complete parts (a) through (e). (a) Identify Ho and Ha. Choose the correct answer below. O A. Ho: µ= 870 (claim) Ho: u5870 Ha: H> 870 (claim) Hai H#870 O C. Ho: H> 870 (claim) Ha: HS870 Ο D. H : μs 900 Ha:H> 900 (claim) ΟF H0: μ= 900 Ha:H#900 (claim) O E. Ho: H> 900 (claim) Ha: us 900 (b) Find the critical value(s) and identify the rejection region(s). Select the correct choice below and fill in the answer box within your choice. Use technology. (Round to two decimal places as needed.) O A. The critical values are ± O B. The critical value is

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