1. Please answer the questions below.

l. (15 points) In a study of the effects of prenatal cocaine use on infants, the following sample m were obtained for weights at birth: 11 = 190, mean = 2700 grams, standard deviation = 645 grams. Assume the sample has been selected from a normally distributed population. Use a 0.01 signicance Ievel to test the claim that weights of babies born to cocaine users have a mean that is less than the mean of 3 103 grams for babies born to mothers who do not use cocaine. Based on the results, does it appear that birth weights are affected by cocaine use? A. State He: B. State H]? C. Is this a one or two-tail test? Why? D. Do you compute a z-statistic or t-statistic and why? B. What is (are) the critical value(s)'? F. What is the decision rule? 6. Calculate the statistic: H. What is your decision regarding Ho and why? interpretation of the results: :--r