Which term describes the advancement of arid land toward living and working areas?

What does x represent in the formula for the compound xcl4?

Areaction is first order with respect to reactant x and second order with respect to reactant y. which statement describes the rate law for this reaction?

Why does earth rotate? because earth is formed from cold gases collapsing due to gravity because the matter in the nebula that formed earth was spinning because earth forms more than 99% of the mass of the solar system because the hydrogen atoms inside the nebula fused to form helium