本人对type I, type II error 不是很熟悉 any hints on the follow questions? Thanks.

1.
A psychologist rejected the null hypothesis that there is no difference between freshmen and sophomores on drinking behavior. She used a significance level of .05 (a = .05) what is the probability of Type I error in this case?

2.
A researcher conducted an experiment to assess if students who regularly exercise get higher grades. She found support for her research hypothesis. Could she be making a Type II error? Why or why not?