The balance of oxygen in earth's atmosphere is maintained primarily by which two processes?

a.
photosynthesis and respiration

b.
outgassing and photosynthesis

c.
lightning and fixation by bacteria

d.
the formation of carbonate rocks and outgassing

For problems 29 - 31 the graph of a quadratic function y=ax^2 + bx + c is shown. tell whether the discriminant of ax^2 + bx + c = 0 is positive, negative, or zero.

The function y= x - 4x+ 5 approximates the height, y, of a bird, and its horizontal distance, x, as it flies from one fence post to another. all distances are in feet. complete the square to find and interpret the extreme value (vertex). select two answers: one extreme value and one interpretation.

Suppose your sat score is 2040. a college with an average sat score for admintted students of which of these would most likely be your best option?