Ofira and Firuze want to find out who has the lowest opportunity cost of cooking a meal. Ofira spends two hours cooking a meal and one hour cleaning the kitchen. Firuze finishes cooking a meal in two hours and spends two hours cleaning the kitchen. What concept will Ofira and Firuze use to determine who has the lowest opportunity cost of cooking a meal? Rational Rule for Buyers marginal principle absolute advantage comparative advantage