1- For the past decade rubber powder has been used in asphalt cement to improve performance. A regression of = (MPa) on = (MPa) can be formed based on the following sample data: x 112,3 97,0 92,7 86,0 102,0 99,2 95,8 103,5 89,0 86,7 y 75,0 71,0 57,7 48,7 74,3 73,3 68,0 59,3 57,8 48,5 a) Verify that a scatter plot supports the assumption that the two variables are related via the simple linear regression model. b) Obtain the equation of the least squares line and interpret its slope. c) The largest x value in the sample considerably exceeds the other x values. What is the effect on the equation of the least squares line of deleting the corresponding observation?