According to darwin's theory of evolution, the plants and animals best suited to an environment survive and reproduce, which is known as

Chalk is an ionic compound. which is a property of all ionic compounds that makes chalkboard? particularly useful for writing on a a high melting point hardness and brittleness inability to dissolve in water a multicolored appearance

Moving down the ramp from 6 meters to

Several billion years ago which gas was the least prevailant in the atmosphere