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Question 4 Section A: The National Association for the Organization of Outhouse Races has narrowed down the choices for their upcoming tournament to the six cities A, B, ..., F. Depending on the existing facilities, the costs to organize games in different cities differ. In particular, it costs (in millions of dollars) $5, $4, S6, 83, 82, & $7 to make the necessary adjustments to the facilities. These costs are borne by the League. The beneficial economic effects in the cities (again in millions of dollars) are $20, $15, $21, $18, $16, & $23, respectively. (a) Formulate a model that chooses cities for the tournament, so as to minimize the total costs, while keeping the economic benefit at a total of at least 72. Define the variables carefully. (b) Formulate: choose at least three cities for the tournament. (C) Formulate: If city Bis chosen, then city Dmust be chosen as well. (d) Formulate: cities E& Fcannot both be chosen