An example of a free good is water in the ocean.
A free good is a good that is available in unlimited supply and does not require any payment or exchange to obtain it.
In the case of water in the ocean, it is freely available and accessible to anyone. It is not owned by anyone and does not require any payment to access or use it. Therefore, it can be considered a free good.
On the other hand, free education, dinner you did not pay for, and your rented apartment are not examples of free goods.
Free education typically refers to education that is provided without direct payment by the student. While it may be free for the student, someone is still paying for it, such as the government or private institutions.
A dinner that you did not pay for may seem free to you, but someone, such as a friend or a host, is still paying for it. The cost of that dinner is borne by someone else, even if it is not you.
Similarly, a rented apartment is not a free good because it involves a transaction where you pay for the use of the apartment. You enter into a contractual agreement with the landlord and pay rent in exchange for living in the apartment.