A company that manufactures computer chips wants to use a multiple regression model to study the effect that two variables have on y, total daily production cost (in 1000s of dollars). Those two variables are the following. x = daily production volume (in 1000s of units) x, =daily amount of time involved in production (in hours) If a regression model is estimated using 64 observations on each of these variables, what are the degrees of freedom (df) for the regression sum of squares, error sum of squares, and total sum of squares? (a) df for the regression sum of squares: (b) df for the error sum of squares: (c) df for the total sum of squares: X