IQ scores from the general population form a normal distribution with a m = 100 and s = 15. However, data indicate that childrens intelligence may be affected if their mothers have German measles during pregnancy. Using hospital records, a researcher obtained a sample of n = 25 school children whose mothers all had German measles during their pregnancies. The average IQ for this sample was x = 96.4. Do these data indicate that German measles have a significant effect on IQ? Test with p=.01.

What is the mathematical format of the alternative and null hypothesis? What is the decision rule? What is the level of significance used?