Answer:
Answer to #1, is D.
Explanation:
The theory of plate tectonics states that the Earth's solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere, the molten upper portion of the mantle. This is also, a theory with the ring of fire.
The answer is "Cold Front".
A cold front is characterized as the change zone where a cool air mass is supplanting a hotter air mass. Cold fronts for the most part move from northwest to southeast. The air behind a cold front is recognizably colder and drier than the air in front of it.
Answer:
Crystal structure
Explanation:
The repeated pattern of similar particles in a material is called crystal. Crystal structure is the largest constituent unit of a solid matter.
The fundamental identity of a crystal structure is a unit cell that is formed by the arrangement of atoms or ions in a particular manner. A crystal is defined as a regular, long-ranged repeated arrangement of unit cells.
Crystal have a sharp melting and boiling point and they give a sharp edge on being cut with a knife.
Downward movement under the force of gravity only.