3. In the equation y y-Ax d. 4. In the equation c + + u, what is the estimated value of + i + u, c denotes consumption andi denotes income. What is the residual for the 5 observation if c 53500 and 35 =S475? a. $975 b. $300 c. $25 5. What does the equation f = + IXdenote if the regression equation is y a. The explained sum of squares b. The total sum of squares c. The sample regression function