Suppose that you plot the residuals from a regression of Number of Wins on Payroll for the Dallas Cowboys over the last 20 years and you get the following: residual lagged residual You would conclude that: definitely serially correlated. likely not serially correlated. possibly serially correlated and you would perform a formal test for heteroskedasticity. O possibly serially correlated and you would always perform a correction for serial correlation.QUESTION 3 Serial correlation occurs when: O an omitted independent variable is correlated with the error term. O the error term is correlated across different time-periods. the error term has a non-constant variance. the error term is, on average, equal to zero.Suppose that you plot the residuals from a regression of GDP on the unemployment rate and you get the following: residuals lazzed residuals You would conclude that the error terms are: definitely serially correlated, likely not serially correlated. possibly serially correlated and you would perform a formal test for serial correlation. possibly serially correlated and you would perform a correction for heteroskedasticity