The file P02_35.xlsx contains data from a survey of 500 randomly selected households. a. In an effort to explain the variation in the size of the monthly home mortgage or rent payment, estimate a multiple regression equation that includes all of the potential household explanatory variables. Let X1 represent the family size. Let X2 represent the ownership. Let X3 represent the total income. Let X4 represent the utilities. Let X5 represent the debt. Let X6 represent the location1. Let X7 represent the location2. Let X8 represent the location3. If required, round your answers to two decimal places. For subtractive or negative numbers use a minus sign even if there is a + sign before the blank. (Example: -300) If your answer is zero, enter "0". = + X1 + X2 + X3 + X4 + X5 + X6 + X7 + X8 b. Using the regression output, determine which of the explanatory variables should be excluded from the regression equation.