<span>ore
An ore is a type of mineral or rock which has a high enough concentration of a desirable element such that it's economical to extract that desired element. This means that the actual concentration of metal in an ore varies quite dramatically depending upon the metal. For instance, Bauxite, which is the ore for aluminum contains approximately 15% to 25% aluminum. But for gold, it's not uncommon to profitably extract 1 ounce of gold from several tons of rock.</span>
I think the correct answer from the choices listed above is option 4. I think it is the process of convection that is responsible for the greatest loss of energy from Earth’s surface into space on a clear night. Convection happens when a mass which contains heat energy is in motion. This happens in wind blowing, oceanic currents and other naturally occurring fluid flows.<span />
I think its D im not sure hope this helped
I don't understand this question
It doesn't sound important
