A sample of 300 urban adult residents of a particular state revealed 63 who favored increasing the highway speed limit from 55 to 65 mph, whereas a sample of 180 rural residents yielded 75 who favored the increase. Does this data indicate that the sentiment for increasing the speed limit is different for the two groups of residents?

a. Test H0: p1
p2 versus Ha: p1 p2 using 
.05, where p1 refers to the urban population.

b. If the true proportions favoring the increase are actually p1
.20 (urban) and p2
.40 (rural), what is the probability that H0 will be rejected using a level .05 test with m
300, n
180?