Give the detailed explanation... don't copy from internet.

6. Below is a plot of the estimated residuals (2,) against the independent variable (X). Which of the following least squares assumptions appear to be violated? 100 maidun -50 -100 20 80 100 (a) The conditional distribution of u; given X, is zero (b) Large outliers are unlikely (c) There is homoskedasticity. (d) More than one of the above. 7. Under the least squares assumptions (not including the assumption of homoskedasticity), the OLS estimator for the slope and intercept (a) has an exact normal distribution for n > 30 (b) is the best linear unbiased estimator (BLUE). (c) has a normal distribution even in small samples. (d) is unbiased and consistent. 8. When there are omitted variables in the regression, which are determinants of the dependent variable, Y, then (a) You cannot measure the effect of the omitted variables, but the estimator of your inde- pendent variable is unaffected. (b) This has no effect on the estimator of your independent variable because the omitted variables are not included. (c) This will always bias the OLS estimator of the independent variable. (d) The OLS estimator is biased if the omitted variable is correlated with the independent variable