(a) to-2.30 (b) to-2.45

Our environment is very sensitive to the amount of ozone in the upper atmosphere. The level of ozone normally found is 4.8 parts/million (ppm). A researcher believes that the current ozone level is at an excess level. The mean of 242samples is 5.2 ppm with a variance of 1.001.00. Does the data support the claim at the 0.05 level? Assume the population distribution is approximately normal. Find the value of the test statistic. Round your answer to three decimal places. Specify if the test is one-tailed or two-tailed. Determine the decision rule for rejecting the null hypothesis. Round your answer to three decimal places. Make the decision to reject or fail to reject the null hypothesis.

Molybdenum rods are produced by a production line setup. It is desirable to check whether the process is in control, i.e. equal to 2.2 inches. Let X = length of such a rod. Assume X is approximately normally distributed where the mean and variance are unknown. Take n = 400 sample rods, with sample average length 2 inches with a standard deviation of 0.5 inches. Using α=0.05, find the test statistic of the necessary test to be held and the corresponding critical value?

Our environment is very sensitive to the amount of ozone in the upper atmosphere. The level of ozone normally found is 4.14.1 parts/million (ppm). A researcher believes that the current ozone level is at an excess level. The mean of 66 samples is 4.34.3 ppm with a variance of 1.001.00. Does the data support the claim at the 0.0250.025 level? Assume the population distribution is approximately normal. Step 1 of 5:  State the null and alternative hypotheses.

You wish to test the following claim (HaHa) at a significance level of α=0.01      Ho:μ1=μ2      Ha:μ1≠μ2 You believe both populations are normally distributed, but you do not know the standard deviations for either. However, assume that the variances of the two populations are equal. You obtain a sample of size n1=20 with a mean of ¯x1=55.2 and a standard deviation of SD1=11.3 From the first population. You obtain a sample of size n2=18n2=18 with a mean of ¯x2=48.3  and a standard deviation of SD2=7.2 from the second population.What is the test statistic for this sample? (Report answer accurate to three decimal places.) test statistic = What is the p-value for this sample? (Report answer accurate to four decimal places.) p-value = The p-value is... less than (or equal to) αα greater than αα This test statistic leads to a decision to... reject the null accept the null fail to reject the null As such, the final conclusion is that... There is sufficient evidence to warrant…

a2.2

Our environment is very sensitive to the amount of ozone in the upper atmosphere. The level of ozone normally found is 7.6 parts/million (ppm). A researcher believes that the current ozone level is not at a normal level. The mean of 1313 samples is 7.2 ppm with a variance of 0.49 Assume the population is normally distributed. A level of significance of 0.02 will be used. Make the decision to reject or fail to reject the null hypothesis.

The mean tensile strengths of 4 different cotton blends (blends 1,2, 3, 4) are being compared using an Analysis of Variance (ANOVA). For each blend, a random sample of s = 20.0, s, = 25.5, s size n = 11 fabric squares is taken. The sample variances are %3D = 24.3, s 30.5. Given that the value of s2 =8.8, calculate the value of the ANOVA test statistic. Enter your answer to two decimal places. Hint: one can check by the definition that the following is true: (1) Treatment of mean squares: MSTrt = n s2. (2) Error of mean squares: M SE = E, s = s + s+ s + s.