The birth weights for two groups of babies were compared in astudy. In one group the mothers took a zinc supplement duringpregnancy. In another group, the mothers took a placebo. A sampleof 98 babies in the zinc group had a mean birth weight of 3423grams. A sample of 80 babies in the placebo group had a mean birthweight of 3004 grams. Assume that the population standard deviationfor the zinc group is 686 grams, while the population standarddeviation for the placebo group is 783 grams. Determine the 98%confidence interval for the true difference between the mean birthweights for \"zinc\" babies versus \"placebo\" babies.
Step 1 of 2:
Find the critical value that should be used in constructing theconfidence interval.
Step 2 of 2:
Construct the 98%confidence interval. Round your answers to thenearest whole number.
