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How are gross production and net production different? a. net production is always greater than gross production. b. net production is always less than gross production. only animals have net production. d. only plants have net production. select the best answer from the choices provided

In many humans, exposing the skin to sunlight over prolonged periods of time results in the production of more pigment by the skin cells (tanning). this change in skin color provides evidence that -

If you relate the doppler effect on sound to the color of light waves, a police car would be the color as it approaches and the color as it recedes away from the observer.