A consumer group claims that the mean annual consumption of coffee by a person in the United States is 23.2 gallons. A random sample of 90 people in the United States has a mean annual coffee consumption of 21.6 gallons. Assume the population standard deviation is 4.8 gallons. At α = 0.05, can you reject the claim?
(a) Identify the claim and state H0 and Ha,
(b) Find the standardized test statistic z,
(c) Find the P-value,
(d) Decide whether to reject or fail to reject the null hypothesis,
(e) Interpret the decision in the context of the original claim. |

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