Final answer:
The answer includes factors that can make an agreement unenforceable such as fraud, illegality, and duress. It emphasizes the role of contractual rights in economic transactions, using the example of a surgeon's employment agreement to illustrate the importance of legal enforcement of contracts.
Step-by-step explanation:
The situations which may render an agreement unenforceable are b) Fraud, mistake, illegality, and impossibility, as well as c) Duress, undue influence, misrepresentation, and mistake. Factors like mutual consent, legality, capacity, and consideration are actually necessary elements for an enforceable contract. Contractual rights are based on property rights and provide individuals with the ability to enter into agreements regarding the use of their property, with recourse through the legal system in the case of noncompliance. For instance, in an employment agreement, if a skilled surgeon operates on a patient and the patient fails to pay, this would be considered theft of property—specifically, the services provided by the surgeon. A legal system that enforces contracts prevents such theft and thus encourages the formation of agreements necessary for economic growth.