Black Russian Terriers is 70.3 cm, with a standard deviation of 2.54. A researcher believes that,...

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Black Russian Terriers is 70.3 cm, with a standard deviation of 2.54. A researcher believes that, because of changes to breeding practices, the true standard deviation, o, is not 2.54. To test this, she selects a random sample of 28 mature Black Russian Terriers and finds that their mean height is 70.4 cm, with a standard deviation of 3.37. Do these data provide enough evidence, at the 0.01 level of significance, to reject the claim that the standard deviation of mature Black Russian Terriers' heights is equal to 2.54? Assume that the heights of mature Black Russian Terriers are approximately normally. distributed. Perform a two-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places. (If necessary, consult a list of formulas.) (a) State the null hypothesis Ho and the alternative hypothesis H. H H (b) Determine the type of test statistic to use. P x 1 S Chi-square Degrees of freedom: (c) Find the value of the test statistic. (Round to three or more decimal places.) (d) Find the two critical values. (Round to three or more decimal places.) and and (e) Can we reject the claim that the standard deviation of mature Black Russian Terriers' heights is equal to 2.54? O Yes No OSO Black Russian Terriers is 70.3 cm, with a standard deviation of 2.54. A researcher believes that, because of changes to breeding practices, the true standard deviation, o, is not 2.54. To test this, she selects a random sample of 28 mature Black Russian Terriers and finds that their mean height is 70.4 cm, with a standard deviation of 3.37. Do these data provide enough evidence, at the 0.01 level of significance, to reject the claim that the standard deviation of mature Black Russian Terriers' heights is equal to 2.54? Assume that the heights of mature Black Russian Terriers are approximately normally. distributed. Perform a two-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places. (If necessary, consult a list of formulas.) (a) State the null hypothesis Ho and the alternative hypothesis H. H H (b) Determine the type of test statistic to use. P x 1 S Chi-square Degrees of freedom: (c) Find the value of the test statistic. (Round to three or more decimal places.) (d) Find the two critical values. (Round to three or more decimal places.) and and (e) Can we reject the claim that the standard deviation of mature Black Russian Terriers' heights is equal to 2.54? O Yes No OSO