Why is it useful to know the background level of extinction? It is part of the scientific process to observe changes in nature.

If current rates greatly exceed background rates, scientists say there is a chance of a
mass extinction event happening.

NOAA and FWS are required by law to compare background rates to current rates.

Scientists want to see if increased extinction rates will threaten the human population.

Nonmetal halogen family atmoic mass 35

What is the oxidation state of an individual bromine atom in nabro3?

To find the work done, the force exerted and distance moved are multiplied. a couch is moved twice before you are happy with its placement. the same force was used to move the couch both times. if more work is done the first time it is moved, what do you know about the distance it was moved? a) when more work was done, the couch was moved the same distance. b) when more work was done, the couch was moved less. c) when more work was done, the couch was moved further. d) when more work was done, the couch wasn't moved at all.