To find out the number of water molecules produced simply use Avogadro’s constant, where 1 mol of any compound is equal to 6.02 x 10^23 molecules of the substance.
Multiply 0.815 to this value.
I believe the answer is the poles of the magnet.
Benzene is more stable because it contains a ring and therefore an aromatic compound. On the other hand, 1,3,5-hexatriene, as a straight-chain alkene, is aliphatic. Aromatic compounds in general are more stable than their aliphatic counterparts because pi electrons are part of a conjugated system, meaning they are "shared" amongst all double-bonded atoms.