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2. (True/False) Identify whether the following statements are true or false and present reasons why you believe so. Follow the notation in the lecture. (a) If the sample size is large, OLS estimators are BLUE (Best Linear Unbiased Estimator) without homoskedasticity. (b) The normality assumption of the regression error can be informally tested by examining the normality of the dependent variable. (c) Consider a model with three independent variables: Y=0+1X1+2X2+3X3+U. Suppose X2 and X3 are highly correlated, but X1 is completely uncorrelated with both X2 and X3. Then Var(^1)=(Xi1X1)22 following the notation from the lecture. (d) Suppose the true population model is Y=0+1X1+2X12+U that is, the second independent variable is the square of the first independent variable. Suppose we know that 2=0 but we inadvertently omit X12. Then there is an endogeneity