If you have ever taken part in a community beach clean, you will know that plastic is far and away the most common substance that washes up with the waves. There are three reasons for this: plastic is one of the most common materials used for making virtually every kind of manufactured object from clothing to automobile parts; plastic is light and oats easily so it can travel enormous distances across the oceans; most plastics are not biodegradable (they do not break down naturally in the environment), which means that things like plastic bottle tops can survive in the marine environment for a long time. (A plastic bottle can survive an estimated 450 years in the ocean and plastic
shing line can last up to 600 years.) While plastics are not toxic in quite the same way as poisonous chemicals, they nevertheless present a major hazard to seabirds,
sh, and other marine creatures. Is this example a case of negative or positive externality? Explain your answer; discuss what environmental policy should be in place, and explain how it would a¤ect the social welfare. Use a graph to explain your answer [carefully label your graph].