2. A political scientist is interested in explaining support for tax reform among U.S. adults. She believes that political party may affect levels of support and previous research suggests specifically that Democrats support tax reform and Republicans don't. But she also wonders if party support for tax reform may be affected by income. Survey data is collected randomly for 300 U.S. residents age 18 and over and is presented below. (Z) Income Level (X) Party (Y) Support Tax Reform? Number of people. High Rep Yes 40 High Rep No 40 High Dem Yes 10 High Dem No 10 Low Rep Yes 27 Low Rep No 33 Low Dem Yes 113 Low Dem No 27 Totals: Rep. Yes - 67 Rep. No - 73 Dem. Yes - 123 Dem. No - 37 C. What are the dependent variable and its level of measure