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Question 4 1 pts A random sample of1o students selected from the student body of a large university had an average age of 25 years and a standard deviation of 2 years. We want to determine if the average age of all the students at the university is signicantly more than 24. Assume the distribution of the population of ages is normal. The test statistic is 2.0. 0 True 0 False Question 5 1 pts A grocery store has an average sales of $8000 per day. The store introduced several advertising campaigns in order to increase sales. To determine whetheror not the advertising campaigns have been effective in increasing sales, a sample of 64 days of sales was selected. It was found that the average was $8300 per day. The sample standard deviation is $1200. The critical value fora level of signicance of .10 is 2.387. 0 True 0 False Question 6 2 pts A light bulb manufacturer claims that the average life oi their light bulb is more than 1000 hours. To test this claim, a sample of 32 light bulbs had an average life of 1120 hours. Assume the standard deviation is 325 hours. The level of signicance is .10. a. State the null and alternative hypothesis. b. State the critical value. c. Calculate the test statistic. d. What is your decision? Edit Wew insert Format Tools Table 12ptv Paragraphvl B I 2 Av lav Tavl 00v .v [av @vl E. I] El