Answer:
Scientists believe that convection circulation within the mantle helps continents to move. As heat from Earth's innermost layer—the core—transfers to the bottom layer of mantle rock, the rock warms, softens, and rises upward. ... This churning motion in the mantle appears to be a major factor in plate movement.
Explanation:
Option A. is the best answer
Answer:b.CaCl2
Explanation:
A compound is a substance resulting when two or more elements are are chemically bonded together either ionically or covalently in a fixed ratio.
From the given options we can see that the only compound there is CaCl2 which is an ionic compound in the fixed ratio of one calcium ion to two chloride ions.
Other options , Cu,Na and Nd are merely pure substance---Elements
Answer:
b,c,d
Explanation:
gasses exert pressure, all particles of a gas sample move at the same speed. gas particles can exchange kinetic energy when they collide.