[JZ_1]

Does it have anything to do with Endothermic and Exothermic changes?
or the change from a lower energy state to a higher one?

[Mitch]

Perform the experiment and let us know.

[JZ_1]

that is the problem...i don't think i know the answer...but i think i can reason it out....

i chosed "A" because to me it seems like "quickly" implied that it would be friction from the surrounding would be causing the system to be warm, or gaining energy.

Also because the "stretched state" of the balloon is "more unstable" than the unstretched. and the balloon is going from a lower energy state to a higher and unstable one. (endothermic?)

another reason would be because your fingers (and probably lip) are acting on the balloon, giving/ supplying energy to the balloon. the balloon returns by "accepting" the energy.

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However these things could be disputed...

by putting and stretching the balloon on your lip, you would feel warm, because of friction....then i could say that it is giving heat to me...

also, sometimes, giving energy to something else may actually stablize it instead of increasing itz unstableness, its helping to stablize it...

to be honest...i dont know the answer (that is why i'm seeing what the majority think of it)
i am still leaning toward "A for +" ..but i might be wrong. the only thing i am sure of is that it cannot be 0 since something did in fact change...

modified*
it turns out that it is negative..since it would feel hot after the stretching of the balloon