How did changes in the atmosphere effect the hydrosphere and life within it?

Compare and contrast the environmental consequences of reliance on coal with reliance on petroleum.

We're always up for a good laugh, but, seriously, refrain from posting silly or answers. keep the quality of high by following the rules and posting thoughtful answers.

What information does a survey provide? a. an accurate description of the population surveyed b. whether there is a predictive relationship between two variables? c. whether there is a cause-and-effect relationship between two variables d. none