1. Give examples of global environmental issues that affect national borders and briefly explain how these issues are addressed.
2. Briefly explain what would happen if parties imposing a negative externality on others had to take the board social cost into account.
3. In the context of both positive externalities and public goods, briefly explain why private firms or individuals might fail to make expenditures or investments that would produce broad social benefits.
4. Briefly compare the wage rates and productivity levels of unionized workers and nonunionized workers in the United States.

ATTENTION> PLEASE DON'T USE ANYBODY ELSE'S WORK OR COPY AND PASTE FROM THE INTERNET !! VERY IMPORTANT.. Use your own words. THANKS FOR YOUR HELP!