IQ Scores 2323223 99 Medium Lead Level High Lead Level 72 = 11 92 x2 = 90.347 85 90 $2 = 9.923 97 83 92 99 111 91 Listed in the data table are IQ scores for a random sample of subjects with medium lead levels in their blood. Also listed are statistics from a study done of IQ scores for a random sample of subjects with high lead levels. Assume that the two samples are independent simple random samples selected from normally distributed populations. Do not assume that the population standard deviations are equal. Complete parts (a) and (b) below. Click the icon to view the data table of IQ scores. a. Use a 0.05 significance level to test the claim that the mean IQ scores for subjects with medium lead levels is higher than the mean for subjects with high lead levels. What are the null and alternative hypotheses? Assume that population 1 consists of subjects with medium lead levels and population 2 consists of subjects with high lead levels. A. Ho: H H: H1 H2 C. Ho: H SH H: H1 H2 O B. Ho H#l H: H1 H2 OD. Ho: H H: H1 H2