In the past, a chemical plant has produced an average of 1200 lb of chemicals per day with a standard deviation of 300 lb. Records of the daily production show the distribution to be normal. A company executive suspects that the average daily production has dropped, and he selects a random sample of 20 operating days. Use a significance level of 0.05 to answer the questions below. 1. What is the null hypothesis for this one-sample hypothesis test? 2. What is the alternative hypothesis? 3. Perform the one-sample test. 4. What is the z-value? What is the p-value? 5. Do you retain or reject the null? Why? 6. What is your conclusion?

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