The Bureau of Alcohol, Tobacco, and Firearms (BATF) has been concerned about lead levelsin California wines. In a previous testing of wine specimens, lead levels ranging from 50 to 700parts per billion were recorded. How many wine specimens (at the least) should be tested if theBATF wishes to estimate the mean lead level for California wines to within 10 parts per billionwith 95% confidence?

Five samples of a ferrous-type substance were used to determine if there is a difference between a laboratory chemical analysis and an X-ray fluorescence analysis of the iron content. Each sample was split into two subsamples and the two types of analysis were applied, with the accompanying results. Assuming that the populations are normal, test at the 0.02 level of significance whether the two methods of analysis give, on the average, the same result. Click here to view the sample analyses. Click here to view page 1 of the table of critical values of the t-distribution. Click here to view page 2 of the table of critical values of the t-distribution. Let sample 1 be the X-ray fluorescence results and let sample 2 be the laboratory chemical results. State the null and alternative hypotheses. Ho: HD H1: HD + Identify the critical region. Select the correct choice below and fill in the answer box(es) to complete your choice. (Round to three decimal places as needed.) O A. t> В. t O C. t<

An organization monitors many aspects of elementary and secondary education nationwide. Their 2000 numbers are often used as a baseline to assess changes. In 2000, 23​% of students had not been absent from school even once during the previous month. In the 2004 ​survey, responses from 7792 randomly selected students showed that this figure had slipped to ​22%. Officials would be concerned if student attendance were declining.  Please refer to the following images:

Samples of body temperatures were taken from both men and women. The information from the samples is summarized below. Use a 0.05 significance level to to test the claim that men and women have different mean body temperatures. Men: n₁ = 15; 1 = 98.38° F; s₁ = 0.45°F Women: n2=91; 2 = 98.17°F; $2 = 0.65° F a. On your Work Upload or Calculations page, write down your hypotheses. Label which hypothesis is the claim. b. The test statistic is c. The critical value is . (Round to 3 decimal places.) (Round to 3 decimal places.) d. The p-value is (Round to 3 decimal places.) e. On your Work Upload or Calculations page, show how you made your decision using either the traditional or p-value method. The correct decision is to 1: Reject the null hypothesis, or 2: Fail to reject the null hypothesis. box.) (Type 1 or 2 in the f. On your Work Upload or Calculations page, write your conclusion/results summary. (Use the standard language about evidence and support of claims.)