Acustom impression tray should fit and adapt well to the model and should maintain mm of impression material between itself and the teeth.

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.

Why is the statement not a hypothesis? sunflowers require soil and plenty of sunlight and water to grow and thrive.

How are fossils most commonly formed