n =25 children who attended day care before starting school had an average score of M = 87 with SS = 1536 on a standardized math test for which the population mean is M= 81.
a. Is this sample sufficient to conclude that the children with a history of preschool day care are significantly different from the general population? Use a two tailed test with = .01.
b. Compute Cohen's d to measure the size of the preschool effect.
c. Write a sentence showing how the outcome of the hypothesis test and the measure of effect size would appear in a research report.