Human health
(b) Terrestrial ecosystems
(c) Marine ecosystems
(d) Identify and describe ONE alternative to ozone-destroying chemical
compounds.
(e) Identify and briefly describe ONE international treaty that addresses the
release of chemical compounds that destroy stratospheric ozone.
- The chart below shows the average American life span for the past 160
years.
(a) In 1840, the life span of the average American was just 37 years. Today,
it is approximately 79 years, with much of the increase in average life
span occurring in the last 50 years.
(i) List TWO events that have occurred within the last 100 years that
could account for the increase in the human life span.
(ii) Choose ONE of the events you selected in (i) and describe in detail
its role in increasing the average human life span.
(b) Currently, about 3.2 billion people—almost half of the world’s population
