Which is characteristic of soil horizons?

A. Boundaries between soil horizons are usually transitional rather than sharp.
B. All of these
C. They are classified by letters.
D. They can be distinguished from one another by appearance and chemical composition.

If we represent the solar system on a scale that allows us to walk from the sun to pluto in a few minutes, then a) the planets are microscopic and the stars are millions of miles away. b) the planets are the size of basketballs and the nearest stars are a few miles away. c) the planets are marble size or smaller and the nearest stars are thousands of miles away.

During metamorphic processes, increased pressure and temperature can affect the of minerals in rock. rocks subjected to very high pressure are typically than others because mineral grains are squeezed together, and the atoms are more closely packed. during metamorphic processes, water facilitates the transfer of ions between and within minerals, which can the rate at which metamorphic reactions take place. the growth of new minerals within a rock during metamorphism has been estimated to be about per million years. metamorphism is commonly associated with convergent plate boundaries, where two plates move toward each other. during contact metamorphism, a large intrusion will contain thermal energy and will cool much more slowly than a small one. metamorphosed sandstone is known as the metamorphic rock made from metamorphosed shale, was once used to make blackboards for classrooms

The earth rotates on its axis and revolves around the sun every