1. How is ozone measured in the atmosphere? What are the units of measurement? How long have we been monitoring ozone levels in the stratosphere?

2. We have naturally occuring ozone in the stratosphere. True or False? If true, how does it occur? Do we have naturally occuring ozone in the troposphere?

3. What are CFC's? What are the effects of incread CFC's on stratospheric ozone? Do we want high or low levels of ozone in the stratosphere? In the troposphere?

4. What is the link between increased skin cancer risk and ozone depletion? What is the common link between ozone depletion and global warming?

5. How have governments responded to the risks associated with ozone depletion? Is that response working?