If you were standing (outside, at noon, on a cloudless day) on the equator during the Autumnal or Vernal Equinox, you would have no shadow because:
O Peter Pan stole it
O The sun is directly over the equator
O The sun's rays are so weak at this time of year that they don't cause objects to cast shadows
O Trick question, there is 24 hour darkness on the equator during the Equinox

The following image is of a diatom. it lives in water and gets food from photosynthesis. it is encased in a hard shell made of something similar to glass or sand . a diatom is a(n) because it has a) multi-celled organism; specialized parts. b) vertebrate; a skeleton. c) insect; an exoskeleton. d) single-called organism; only one cell.

The kidney filters potentially toxic substances in the blood, and thus “clears” the blood of those substances. this clearance function is dependent upon and proportional to the diffusion gradient of the substance across filtering capillaries, i.e. if the concentration of the substance is doubled, twice as much will be cleared from each ml of blood that is filtered. suppose that the body produces a constant amount of a substance x per unit of time. the kidneys eliminate substance x at a rate directly proportional to the concentration of the substance and the volume of blood cleared each minute (c): elimination = c × [x], where [x] is the steady-state concentration of substance x. imagine an individual with an initial concentration of x equal to [x]0 who develops kidney disease. her baseline clearance c0 drops to one half of the original (½c0). what is the new steady state concentration of x? (for simplicity, assume that substance x is 100% filtered by the kidney).

According the inverse square law, doubling the distance from the source of the sound, a speaker, for example, will drop the sound 6 db each time. if you were standing in the back of an auditorium, 32 feet away from a speaker not using any amplification, would you be able to hear a speaker clearly? why or why not?