The hypothesis test H0:μ=176.6 H1:μ≠176.6 is to be carried out for a population where ?σ is not known. A random sample of 39 has a mean of 173.8 and yields the test statistic of tc=−1.43328. What was the standard deviation of the sample? s =

E= Over the years, the mean customer satisfaction rating at a local restaurant has been 65. The restaurant was recently remodeled, and now the management claims the mean customer rating, u, is not equal to 65. In a sample of 32 customers chosen at random, the mean customer rating is 76.2. Assume that the population standard deviation of customer ratings is 22.8. Is there enough evidence to support the claim that the mean customer rating is different from 65? Perform a hypothesis test, using the 0.10 level of significance. (a) State the null hypothesis H, and the alternative hypothesis H,. Ho Aa O