Consider three possible areas for applying a tradable permit system: Runoff of nitrates in the Mississippi River basin (see http://graphics.wsj.com/mississippi/ (Links to an external site.) for more detail) Mercury emissions from coal-fired power plants (see https://www.epa.gov/mats/cleaner-power-plants#controls (Links to an external site.) the current plan is to set a standard for mercury) Shrimp, an important natural resource found in the waters off the coast of South Carolina (see http://www.dnr.sc.gov/marine/pub/seascience/shrimp.html (Links to an external site.) for background on shrimp in South Carolina) Which of these do you think presents the greatest opportunity from shifting from a standard based regulation to a tradable permit system and why? Describe briefly how such a system might work in this case, including who would get permits, the size of net benefits from controlling emissions (or overharvesting in the case of shrimp) resulting from a more cost effective regulation, and what you think the greatest challenge to implementing such a system might be. Present your ideas in about 350-400 words.