For a Sample of 500 College Professors,the Estimated Regression Equation

Multiple Choice

For a sample of 500 college professors,the estimated regression equation is given by = 275 - 3x - 2D,where y is the retirement age,x is pre-retirement annual income (in $1,000s) ,and D is a dummy variable that takes the value of 0 for male professors and 1 for female professors.Assume that there is a relationship between y,x,and D.For male professors with pre-retirement income of $70,000,the average age of retirement is:

A) 75
B) 70
C) 65
D) 60