I Would think it would be C Since Humans can't live 500 years but then yet again it is light years not regular years i think if you find how man years is 500 light years the that could help you in finding the answer
Molecular wt if ethene = 28 g/mol
take 14 ÷ 28 = 0.5 mol
since there is a 1:1 ratio between ethene and ethanol one should produce 0.5 mol
MW ethanol = 46
0.5 × 46 = 23 g should be produced.
17.25/23 = 0.75 = 75% Percent yield
It moves up and away from the pan, with the hottest particles