Answer the following questions keenly and give the correct answer to all the question

Consider Y = KB + a. Show that with uncorrelated errors with constant variance, the generalized least squares estimator is equivalent to the ordinary least squares estimator. Suppose we have the model: Y=beta0+betal*X1+beta2*X2+beta3*X3+beta4*X4 +beta5*X5+u X1 is a continuous variable X2=X1*X1 X3 is a binary variable X4 is a binary variable X5=X3*X4 We estimate the model by OLS and obtain the estimates of the betas. Refer to the model above. The general form for the effect of X3 on Y is given by: a)beta3hat+beta5hat b) beta3hat+beta4hat+beta5hat c) None of the above d) beta3hat*X3 e) beta3hat+beta4hat f) beta3hat g) beta3hat*X3+beta5hat*X3*X4 h) beta3hat+beta5hat*X4Chapter.3: The Political and Legal Environments Facing Business 1. Define political system and explain why a business manager should study the political system of a country. 2. How does democracy differ from totalitarianism? Will the conduct of business be different in the two systems? How? 3. Describe how the political ideologies are changing in the world. How a manager can adapt to such changes? 4. What is political risk? How can we manage political risk? 5. Discuss the Types Legal Systems and their implications in international business. Chapter 4: The Economic Environments Facing Businesses 1. Define "economic freedom" and explain its implication in an economy. 2. What are the three types of economic systems? What criteria can we use to evaluate them? Explain each system using the criteria discussed in class. 3. Discuss the impact of "emerging nations" and explain how they will affect international business. A. Explain how we can evaluate an economy using traditional and nontraditional (broader) measures of economic performance. 5. Explain the Balance of Payments account of a country with its four subheads. Why is it important to in international business manager?Problem 1: Given the model y = XB + with E(E X) = 0 and Var(E X) = 0. 1. Derive the expected value and covariance matrix of the estimator BGLS = (X'9 1X)-'X'n ly. (1) 2. Consider the case where you have the model discussed here, but instead of using (1) to estimate S you applied the OLS estimator. Please derive the expected value and covariance matrix of the OLS estimator under the model assumptions given in this problem. Is OLS biased in this setting? Is it efficient