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How many moles are in 250 grams of tungsten (w)? * 4.4x10^23 moles 4.2x10^23 moles 0.7 moles 1.4 moles

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.

Reduction is a reaction which results in a in electrons and a in positive charge of the atom or ion 1) a- loss 1) b- gain 2) a-increase 2) b-decrease