Assume a sample of 144 observations is selected from a norma

Assume a sample of 144 observations is selected from a normal population. The sample mean is 212 and the sample standard deviation is 14. Conduct the following test of hypothesis using the .05 significance level. Null Hypothesis: The population mean is greater than or equal to 215. Alternative Hypothesis: The population mean is less than 215. What is the decision rule? What is the value of the test statistic?

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