A random sample of data was collected on residential sales in a large city. The dependent variable is the sale price (Y) and the independent variables are area (X1) and location (dummy variable Z1 and Z2 defined as follows:) Z1 = Z2 = 0 for intown Z1 = 1, Z2 = 0 for inner suburbs Z1 = 0, Z2 = 1 for outer suburbs After analyzing the data, the following equation for the overall model was obtained Y with hat on top space equals 8.96861 plus 4.80699 X subscript 1 plus 52.12239 Z subscript 1 plus 48.55824 Z subscript 2 minus 3.20121 X subscript 1 asterisk times Z subscript 1 minus 2.80309 X subscript 1 asterisk times Z subscript 2 S S R space left parenthesis X subscript 1 right parenthesis space equals 2271.71350 S S R space left parenthesis X subscript 1 space Z subscript 1 space Z subscript 2 right parenthesis space equals 2607.73276 S S R space left parenthesis X subscript 1 comma space X subscript 1 asterisk times Z subscript 1 comma space X subscript 1 asterisk times Z subscript 2 right parenthesis space equals space 2437.67749 S S R space left parenthesis X subscript 1