The IQ scores for a random sample of subjects with low lead levels in their blood and another random 1 ll n i s in sample of subjects With high lead levels in their blood were collected. The statistics are summarized in H Low Lead Level \"1 75 93.33468 1591514 the accompanying table. Assume that the two samples are independent Simple random samples .. . selected from normally distributed populations Do not assume that the population standard deviations \"'9\" Lead LEVE' \"2 23 35 55783 9 05532 are equal. Complete parts (a) to (c) below. a. Use a 0 01 Significance level to test the claim that the mean IQ score of people with low blood lead levels is higherthan the mean IQ score of people with high blood lead levels. What are the null and alternative hypotheses? Assume that population 1 consists of subjects With low lead levels and population 2 consists of subjects With high lead levels. ' A- Hoi l~l1 = 1'2 ' 3- Hoi 1'1 = H2 H12u1>p2 H12|I1i|l2 .1 C. Hg'u1i u2 22': D. HD: p1 j|2 H1'li1>l'2 \"with\"? The test statistic is . (Round to two decimal places as needed.) The Pvalue is (Round to three decimal places as needed.) State the conclusion for the test. .1 A. Reject t1e null hypothesrs. There is sufficrent evidence to support the claim that subjects With low lead levels have higher IQ scores. ..\\ B. Fail to reject the null hypothesis. There is sufficient evidence to support the claim that subjects with low lead levels have higher IQ scores. .1 C. Reject he null hypothesis. There is not sufficient evidence to support the claim that subjects with low lead levels have higher IQ scores. I D. Fail to reject the null hypothesis. There is not sufficient evidence to support the claim that subjects with lowr lead levels have higher IQ scores. b. Construct a confidence interval appropriate for the hypothesis test in part (a). * H1 - 12* (Round to one decimal place as needed.) c. Does exposure to lead appear to have an effect on IQ scores? because the confidence interval contains