Consider the distribution of hemoglobin levels for the population of children under the age of 6 who have been exposed to high levels of lead. This distribution has an unknown mean and a standard deviation = 0.85 g/100 ml. We select a sample of 74 children who have been exposed to high levels of lead; the children have a mean hemoglobin level of 10.6 g/100 ml. a) Calculate a 95% CI for . b) Provide a practical interpretation for the interval constructed in (a). c) Explain what would happen to the width of the confidence interval constructed in (a) if: (i) the confidence level decreased, holding all else constant. (ii) the population variance decreased, holding all else constant. (iii) the sample size decreased, holding all else constant.