Acandidate for one of ohio's two u. s. senate seats wishes to compare her support among registered voters in the northern half of the state with her support among registered voters in the southern half of the state. a random sample of 2000 registered voters in the northern half of the state is selected, of which 1062 support the candidate. additionally, a random sample of 2000 registered voters in the southern half of the state is selected, of which 900 support the candidate. a 95% confidence interval for the difference in proportion of registered voters that support this candidate between the northern and southern halves of the state is: