A random sample of 200 undergraduate students majoring in political science has 110 women. A random sample of 200 undergraduate students majoring in dietetics has 140 women. Regard these as independent random samples from the populations of students majoring in political science and dietetics respectively in answering the questions below. Let p1 and p2 denote the respective population proportions of women in two populations, those majoring in political science, and those majoring in dietetics.

1)From these two samples, the difference between 2 sample proportions, p1-p2 is

2)The standard error of the sampling distribution of p1-p2 is