1. Human-caused (anthropogenic) emissions of CO2 are only about 3 percent of total CO2 emissions each year. (Oceans are the biggest emitters.) Why is so much attention directed at anthropogenic emissions of CO2?
2. How come we worry about extinction of fish but not about the extinction of dogs, cats, or cattle? What is going on to create this difference?
3. Why do you suppose the federal government gives special treatment to owners of fertile farmland rather than, say, to automobile mechanics? Explain. 
4. Some states require that retailers collect (refundable) deposits on cans and bottle they sell. The amount is always greater than the value of the can or bottle. How do the deposits affect the incentives of individuals to recycle these products? Does the size of the deposit fee matter? How high should it be