20. A conditional strategic move, such as a threat or promise, can be credible only if a. rivals believe the manager making the threat or promise can be trusted to follow through on any commitment, threat, or promise that he or she makes. the strategic move harms rivals. it can increase each firm's payoff. when the time comes to carry out the threat or promise, fulfilling the threat or promise is in the best interest of the firm making the threat or promise. none of the above. 21. When United Airlines gives a $30 fare discount to persons with student IDs, they are practicing first-degree price discrimination. second-degree price discrimination. third-degree price discrimination markup pricing. tying. Price Marginal Cost Demand 100 150 200 Quantity Marginal Revenue 22. Refer to the figure above. At the profit maximizing price the elasticity of demand is -5 -2 -3.33 None of the above