Write the social welfare (social utility) functions discussed in class for the efficiency standard, the sustainability (or equity) standard and the safety standard, explicitly including pollution terms. Be sure to carefully define all variables and functions. Explain the logic behind each function, and explain why we would use each social welfare function. You may assume there are only two individuals in the economy. Explain the marginal effects from each term, whether they are positive or negative effects for social welfare. Additionally, if there are any terms that have an assumed range, make sure to make your assumptions explicit