A measure of the number of particles of a substance in a given volume would be concentration. <span>In chemistry, </span>concentration<span> is the abundance of a constituent divided by the total volume of a mixture. There are a number of ways expressing it such as molarity, molality, normality, ppm, percentage and the like.</span>
Answer: D. Galaxies show a red shift, indicating they are moving away from each other.
Explanation:
Galaxies seem to show a red shift which indicates that the galaxies are moving away from each other. This provides evidence for the Big Bang theory because the theory posits galaxies will keep moving away from each other.
This is because when an explosion happens, matter moves away from the point where the explosion happened. If the Big Bang happened therefore, galaxies will move away from the source which is why galaxies are moving away from each other.
Differences Between Pteridophytes and Seed Plants
Pteridophytes don't produce cones, flowers, or fruit, unlike these seed plants. Instead, Pteridophytes produce spores. Spores are living, single-celled structures that are essential to the life cycle of many plants.
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