(7 points) A manufacturer of detergent claims that the contents of boxes sold weigh on average at least 30 ounces. The distribution of weights is known to be normal with standard deviation 0.7. A random sample of 27 boxes yielded an average weight of 29.7 ounces. Suppose an inspector wants to test the null hypothesis that the population mean weight is at least 30 ounces. That is, test the null hypothesis Ho : H = 30 against the alternative hypothesis Ha : H