Let's look at a COVID-19 vaccine from the economics point of view. There are two ways to think about what the term "vaccine" represents. They are (a) A vaccine formula or a method of producing a given vaccine. At this level, a vaccine is just an idea, a recipe that anyone with a proper equipment can use to produce a vaccine product. (b) An actual vaccine dose in a physical form (e.g. in a vial) that was manufactured by a company. Discuss the rivalry and excludability of these two versions of a good, (a) and (b), and classify them into one of the 4 categories of goods discussed in Lecture 5. Do you think a competitive market will produce an efficient quantity of good (a)? What about good (b)? Carefully explain your reasoning. If one of the goods cannot be produced by a competitive market, what are the possible solutions to this