A uses symbols to represent a chemical reaction and shows the relationship between the reactants and products of a reaction

If you explain it more through i will answer it : )

It’s b. mass i searched it up

The net force is 100

Answerδh > 0explanationc₆h₆  (s)  → c₆h₆ (l)if you are changing it from a solid to a liquid, you are pretty much melting the solid. this requires heat energy. therefore, the reaction is endothermic (takes in energy); the system enthalpy increases as the reaction proceeds: δh > 0.