The upper surface of the zone of saturation is called the water table
<span>The best reason I can think of for why we believe that air is a mixture is that freezing air slowly yields different liquids at different temperatures. Liquid nitrogen has a different boiling point than liquid oxygen. They also freeze at different temperatures. If air were only 1 compound, then air in its entirety would have a single boiling point and a single freezing point. </span>
Answer;
= 0.054 kg or 54 g
Explanation;
Using the equation; Q = mcΔT where Q is the quantity of heat transferred, m is the mass, c is specific heat of the substance, ΔT is delta T, the change in temperature.
ΔT = 75 - 20 = 55 C.
Solve the equation for m
m = Q/ cΔT
Mass = 12500 / (55 × 4200)
= 0.054 kg or 54 g
The radioactive decay of unstable isotopes continually generates new energy within Earth's crust and mantle, providing the primary source of the heat that drives mantle convection. Plate tectonics can be viewed as the surface expression of mantle convection.