Use the given information to find the number of degrees of freedom, the critical values and x, and the confidence interval estimate of o. It is reasonable to assume that a simple random sample has been selected from a population with a normal distribution. Nicotine in menthol cigarettes 95% confidence; n = 21, s= 0.22 mg. Click the icon to view the table of Chi-Square critical values. df = x = x² = The confidence interval estimate of o is (Round to two decimal places as needed.) (Type a whole number.) (Round to three decimal places as needed.) (Round to three decimal places as needed.) mg

Find the critical value t, for the confidence level c = 0.99 and sample size n = 20. Click the icon to view the t-distribution table. ...... (Round to the nearest thousandth as needed.)

Assume that we want to construct a confidence interval. Do one of the following, as appropriate: (a) find the critical value to/2, (b) find the critical value Za/2, or (c) state that neither the normal distribution nor the t distribution applies. Here are summary statistics for randomly selected weights of newborn girls: n=287, x= 29.9 hg, s= 6.8 hg. The confidence level is 90%. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. OA. ta/2= OB. (Round to two decimal places as needed.) Zα/2 (Round to two decimal places as needed.) OC. Neither the normal distribution nor the t distribution applies.

What is one property of a stationary time series?   Question 23 options:   The datapoints demonstrate a clear seasonal pattern   The mean remains constant over time   It is plotted as a straight horizontal line   It demonstrates an upward trend

Researchers studied the mean egg length (in millimeters) for a bird population. After taking a random sample of eggs, they obtained a 95% confidence interval of (45,60). What is the value of the margin of error? Choose the correct answer below. A. 15 mm B. 52.5 mm O c. 7.5 mm O D. 1.96

Assume that we want to construct a confidence interval. Do one of the following, as appropriate: (a) find the critical value t,/2, (b) find the critical value z, 12, or (c) state that neither the normal distribution nor the t distribution applies. Here are summary statistics for randomly selected weights of newborn girls: n = 152, x = 31.1 hg, s= 6.2 hg. The confidence level is 95%. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. ta/2= (Round to two decimal places as needed.) В. Za12 (Round to two decimal places as needed.) C. Neither the normal distribution nor the t distribution applies.