Afew years ago, european medical researchers concluded a study of whether hiv is transmitted by infected mothers to infants via breast milk. the study included 721 babies born to hiv-positive mothers between december 1984 and august 1991 in 19 cities in germany, italy, the united kingdom, spain, the netherlands, sweden, and belgium. 385 of these mothers breast-fed their infants and 75 of their infants became infected by eighteen months of age. 336 mothers bottle-fed their infants, and 29 of these infants became infected by eighteen months of age. using the confidence interval approach, test the null hypothesis that among babies born to hiv-positive mothers, the proportions infected were the same for breast-fed babies (x population) and bottle-fed babies (y population), against the alternative that these proportions are different. use a 1% level of significance.

what are the correct null and alternative hypotheses? which is the correct test statistic to use as the basis for the relevant confidence interval? what is the upper end of the confidence interval? what is the conclusion of the test?