Human activities can have positive and negative effects on the environment. Humans can benefit natural areas by A. throwing waste products in these areas.
B. removing all the vegetation from theses areas.
C. polluting the areas by burning fossil fuels.
D. preserving the natural resources that they provide.

Global warming will produce rising sea levels partly due to melting ice caps but also due to the expansion of water as average ocean temperatures rise. to get some idea of the size of this effect, calculate the change in length (in m) of a column of water 1.45 km high for a temperature increase of 1.12°c. assume the column is not free to expand sideways. as a model of the ocean, that is a reasonable approximation, as only parts of the ocean very close to