To test H0: 6 22.5 versus H]: a>2.5, a random sample of size n = 18 is obtained from a population that is known to be normally distributed. (a) If the sample standard deviation is determined to be 5 = 3.4, compute the test statistic. (b) If the researcher decides to test this hypothesis at the or: 0.10 level of signicance, use technology to determine the Pvalue. (c) Will the researcher reject the null hypothesis? (a) The test statistic is 350 = (Round to two decimal places as needed.) To test H0: 6 = 4.6 versus H1: (sf-4.6, a random sample of size n =13 is obtained from a population that is known to be normally distributed. (a) If the sample standard deviation is determined to be s = 5.7, compute the test statistic. [b] Ifthe researcher decides to test this hypothesis at the a: 0.05 level of signicance, use technology to determine the Pvalue. (c) Will the researcher reject the null hypothesis? (a) The test statistic is 10 2 (Round to two decimal places as needed.) Suppose a mutual fund qualifies as having moderate risk if the standard deviation of its monthly rate of return is less than 3%. A mutual-fund rating agency randomly selects 24 months and determines the rate of return for a certain fund. The standard deviation of the rate of return is computed to be 2.07%. Is there sufficient evidence to conclude that the fund has moderate risk at the o = 0.05 level of significance? A normal probability plot indicates that the monthly rates of return are normally distributed. What are the correct hypotheses for this test? The null hypothesis is Ho: The alternative hypothesis is H1:The piston diameter of a certain hand pump is 0.5 inch. The manager determines that the diameters are normally distributed, with a mean of 0.5 inch and a standard deviation of 0.004 inch. After recalibrating the production machine, the manager randomly selects 28 pistons and determines that the standard deviation is 0.0035 inch. Is there significant evidence for the manager to conclude that the standard deviation has decreased at the a = 0.01 level of significance? What are the correct hypotheses for this test? The null hypothesis is Ho: The alternative hypothesis is H1:Suppose a professional golfing association requires that the standard deviation of the diameter of a golf ball be less than 0.003 inch. 1.682 1.682 1.681 Determine whether these golf balls conform to this requirement at the o= 0.05 level of significance. Assume that the population is 1.677 1.679 1.682 normally distributed. 1.679 1.677 1.682 1.682 1.679 1.678 . . . What are the correct hypotheses for this test? The null hypothesis is Ho: The alternative hypothesis is Hy