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Which of the choices below is one of the primary gases found in the atmosphere? a. helium b. carbon dioxide c. nitrogen d. argon

An ideal polarizer with its transmission axis rotated 30 degrees to the vertical is placed in a beam of unpolarized light of intensity 10w/m^2. after passing through the polarizer, what is the intensity of the beam? a. 8.7 w/m^2 b. 7.5 w/m^2 c. 5.0 w/m^2 d. 10 w/m^2 e. 2.5 w/m^2

Explain earth's motion, using the terms "precession" and "rotation" in your answer.