~~Now, you have left your question very open ended and didn't ask for any particular kind of answer so I'll do my best to get what you're looking for.~~
A physical change in a substance doesn't change what the substance is. It can possibly melt or freeze an object. I mean heat makes things expand while cooling makes them retract.... In chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.
Eg. lets say you have any type of food (lets say chocolate a hard block of one) amd you heat it up it’s obviously going to change the way it is instead of being in its orgianl form it might be melted or gooey, and when you cool it might change shape or texture
So pretty much temperatures can chamge any type of substance into being anything frim mushy, hard, soft, melted,solid, u know
W= FxD. Since the weight is not put into force you’re going to convert it by multiplying it by 9.8 (gravity). 76kg x 9.8 = 7448. Then multiply that by the distance (2.5). Your answer is 1862.
