Ships provide maritime transport services but emit polluting gases such as sulfur oxides which cause air pollution as well as many respiratory diseases in the general population. In 2020, new regulations of the International Maritime Organization (IMO) regarding sulfur oxides were implemented with very significant implications for the shipping industry, while in December 2022 the IMO adopted even stricter regulations for the Mediterranean Sea. a) Explain what type of externality (positive or negative, production or consumption or mixed) in the market for maritime transport services the above case falls under.Then assuming that the market for marine services is perfectly competitive and that there are no property rights in the "common" air, determine the equilibrium quantity of that market as well as the socially desirable quantity and draw a diagram of the above. Compare the two equilibria and justify your answer by also referring to the difference between social and private marginal cost or benafit..