Answer:
His opportunity cost is "loosing the extra time he stays with his friends."
Step-by-step explanation:
Opportunity cost simply refers to that benefit missed as a result of choosing one alternative over the other. In this scenario, Ricardo chooses to take the promotion and forgo spending time with his friends. Opportunity cost is also the same as the forgone alternative. Hence the opportunity cost in this scenario is the time that Ricardo spends with his friends.