INSTRUCTIONS: Show all your work and good luck. Round all solutions to the hundredths place. Perform an appropriate hypothesis test on the mean, . Use the six step process used in class and label each step.

You may use the Critical Region approach or the P-value approach when performing a z-test. You'll need to use the Critical Region approach for a t-test. Due in class on Wednesday, Dec. 7th.

1. Suppose a friend of yours claims the summer of 2020 in Houston, Texas was hotter than usual. To test the claim, you went to AccuWeather.com and randomly selected 12 days in the summer of 2020. You recorded the departure from normal, with positive values indicating above-normal temperatures and negative values indicating below-normal temperatures. Assume temperatures in Houston distribute approximately normally and the population standard deviation of temperatures in summer in Houston is 1.8 degrees. At 5% level of significance, is your friend right that it was hotter than usual?