(PLEASE) highlight the answers - only a short explanation is required.

PART A

An upper-tailed test of significance produces a test statistic that is higher than the critical value. Which of the following conclusions is appropriate? O Fail to reject the null hypothesis. O Reject the alternative hypothesis. O Reject the null hypothesis. O Accept the null hypothesis.Find the critical 1.n'aluel[s]I that correspond to the following situations. Assume we know a, so we can use the standard nonnal distribution. (Use a table or technology. Round your answers to two decimal places.) Ia USE SALT {a} an uppertailed test with a = 0.05 |:| {b} a twotailed test with a = I102 |:| A report states that the average age of commercial airliners in the United States is 11 years with a standard deviation of 2.7 years. A researcher wants to test this claim and finds that a random sample of 40 planes from around the United States has an average age of 12.2 years. At an o = 0.05, can you conclude that the average age of airliners has increased? (a) What is the test statistic for this scenario? (Round your answer to two decimal places.) (b) When a = 0.05, choose the appropriate conclusion for this test. (Use a table or technology.) O Accept the null hypothesis. O Reject the alternative hypothesis. O Fail to reject the null hypothesis. O Reject the null hypothesis.It is claimed that the heights of young men at a large university are approximately normally distributed, with a mean of 69.6 inches. A random sample of heights from the university are listed below (in inches). 74 65 70 76 69 75 70 71 72 70 69 LA USE SALT These data were used to calculate the following sample mean and standard deviation. n = 11 x = 71 5 = 3.1305 Is there sufficient evidence to say that the mean height of men at the university is taller than the claimed 69.6 inches? (a) Assume the conditions are met to perform a t test. Calculate the test statistic. (Round your answer to three decimal places.) t = (b) What is the critical value associated with a one-tailed test when a = 0.1? (Use a table or technology. Round your answer to three decimal places.) (c) Choose the appropriate conclusion for this test. O Fail to reject the null hypothesis. O Reject the null hypothesis. O Reject the alternative hypothesis. O Accept the null hypothesis