What two recurring events in earth's history have an impact on the carbon cycle?

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Which is an important function of normal flora? a. aid with bone marrow production. b. crowd out pathogenic bacteria. c. destroy digestive track pathogens. d. manufacture iron in the bloodstream.

For the strategies below, decide whether they are best described as demand-side solutions or supply-side solutions to meeting human needs for fresh water. remember that a demand-side solution reduces demand for fresh water, whereas a supply-side solution increases the supply of fresh water. (a) damming a river to create a reservoir (b) desalinating seawater (c) a nation invading a neighboring country to access their rivers (d) raising water prices for consumers and businesses (e) providing tax breaks for companies that use less water (f) replacing inefficient irrigation with more-efficient drip irrigation to grow crops (g) requiring low-flow showerheads in all new homes