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Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.

Autonomous underwater explorers will be used to gather large-scale ocean information select the best answer from the choices provided ot

What is the volume of a book that has a width of 10 cm a length that is 2 times the width and a height that is half they would remember to express your answer in keeping units