Question: During the Bush and Obama administrations, there has been a great deal of discussion about partisanship. Did partisanship have an impact on approval ratings in public polls? The following tables display the approval ratings of both presidents during April of their first year in office. The first table shows the approval numbers for each president from voters of his own party (Democrats for Obama, Republicans for Bush). The second table shows the approval numbers for each president from voters of the opposition party (Republicans for Obama, Democrats for Bush). The numbers are comparable to the percentages reported by gallup.com.

a. Test at the 1% significance level whether the approval ratings by their own party voters are related.

b. Test at the 1% significance level whether the approval ratings by the opposition party voters are related.