a) Discuss two possible sources of endogeneity b) To deal with the endogeneity problem, instrumental variable estimation techniques are often utilized. Discuss the two conditions that must be satisfied for an instrument to be considered VALID c) Discuss one problem that may result when Multicollinearity is present in a regression analysis d) The graphs below depict the pth order polynomials for one independent variable. 1. E(y) II. ELM III. ELy iv. Ely . For each graph identify the order of the polynomial (e.g. first order, second order, third order, etc.) . Using the parameters Bos 1, 82, 83, etc., write an appropriate model form relating E (y) to x for each graph