a) Explore the data. i. Describe the age and sex distribution of these children, with reference to appropriate numerical and graphical summaries. ii. Children are considered substantially underweight if, for their height, they are in the lower 5% of the distribution of weight. What percentage of children in this study sam- ple are substantially underweight? iii. What proportion of children (in the study) are iron-deficient? iv. How does the prevalence of anemia in the sampled children compare with anemia prevalence in low-income children in the United States? b) Calculate and interpret an appropriate measure of association between sex and presence of anemia. c) Do the data support the claim that more than half of the female children in this slum area are anemic? Justify your answer. d) Estimate the association between age and presence of anemia. Is an older child more or less likely to be anemic than a younger child? Justify your answer. e) Fit a model to investigate whether the association between age and presence of anemia dif- fers by sex. Interpret the model coefcients and summarize your ndings. 1') Previous research has shown that iron deciency is associated with anemia. i. Compare the odds of being anemic for a child whose iron level is -1.48 mglkg to one whose iron level is 0.18 mglkg. ii. Do these data provide evidence that iron level is significantly associated with the pres- ence of anemia? Explain your answer. iii. Does the association between iron level and anemia persist after adjusting for the pos- sible confounding variables sex, age, weight to height z-score, family wealth quintile, and recent episode of diarrhea? Explain your answer. g) A public health ofcial is about to hold a press conference announcing a decision to admin- ister iron supplementation to all children living in the slum district, based on the results of the previous analysis. You have been asked to prepare the ofcial for questions from the press. In no more than ve sentences, provide answers to the following questions. Be sure to use language accessible to a general audience and fully explain your answers. i. What is the rationale behind the decision to provide iron supplementation to all chil- dren living in this district? ii. Does the study provide evidence that iron supplementation will reduce the prevalence of anemia in this population of children