How much of the US power demands could be met by geothermal resources if they're used was widespread

Why should seat belts not be mandatory quick plz

Which accurately compares concave and convex lenses?

The sun’s mass is 2.0×10^ 30 kg, its radius is 7.0×10 5 km, and it has a rotational period of approximately 28 days. if the sun should collapse into a white dwarf of radius 3.5×10 3 km, what would its period be if no mass were ejected and a sphere of uniform density can model the sun both before and after?