Please help me I do not understand

The answers is a nuclear changes

Idont know. if you want an answer you need to give us some context dude.

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.

The se-ci  bonds is more polar  than s-br bond