Answer: variation, reproduction, and heritability.
Explanation: Genetic variation is an important force in evolution as it allows natural selection to increase or decrease frequency of alleles already in the population. Genetic variation is advantageous to a population because it enables some individuals to adapt to the environment while maintaining the survival of the population.
All species must reproduce to survive. Organisms cannot live forever, so they must reproduce to allow their species to continue to live on. Reproduction is nature's way of allowing a species to survive.
Higher heritability means the trait evolves faster; fewer generations are required for the trait to increase to the same degree as a trait with lower heritability. For this reason, genetic correlation and heritability show how a trait might change from one generation to the next and into the future.
Answer: Potassium-40 decays into argon gas over time.
Explanation: Potassium-argon dating is a dating method used to determine the age of sedimentary rocks by comparing the proportion of K-40 to Ar-40 in a sample of rock, and knowing the decay rate of K-40.
Potassium-40 undergoes decay following first order kinetics as given below:

Cccccccccccccccccccccccccccc
Cell membranes help organisms maintain homeostasis by controlling what substances may enter or leave cells
Answer:
because it cools you off when its too warm and overall gives a sense of calm