URGENT PLS HELP Lead has four naturally occurring isotopes, whose atomic masses are 203.97302 amu, 205.97444 amu, 206.97587 amu, and 207.97663 amu. The relative abundance of these four isotopes is 1.4%, 24.1%, 22.1%, and 52.4% respectively. From these data calculate the atomic but of lead.

There are two steps in the usual industrial preparation of acrylic acid, the immediate precursor of several useful plastics. in the first step, calcium carbide and water react to form acetylene and calcium hydroxide: cac2 (s) + 2h2o (g) → c2h2 (g) + caoh2 (s) =δh−414.kj in the second step, acetylene, carbon dioxide and water react to form acrylic acid: 6c2h2 (g) + 3co2 (g) + 4h2o (g) → 5ch2chco2h (g) =δh132.kj calculate the net change in enthalpy for the formation of one mole of acrylic acid from calcium carbide, water and carbon dioxide from these reactions. round your answer to the nearest kj .