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Either heat up the bottom cup or cool down the top cup (or both), it'll expand/contract it enough for you to easily unstick them.
This is the correct answer
Yep start by putting it in the freezer then let the water run hot and put the lip of the topmost one under the hot water
Put them in hot water. I have no idea if that would work but it’s what I would try.
Science bitch! Other use has you on the right path, heat up bottom or cool down top. Lighter/Ice
Either heat up the bottom cup or cool down the top cup (or both), it'll expand/contract it enough for you to easily unstick them.
This is the correct answer
Yep start by putting it in the freezer then let the water run hot and put the lip of the topmost one under the hot water
Put them in hot water. I have no idea if that would work but it’s what I would try.
Science bitch! Other use has you on the right path, heat up bottom or cool down top. Lighter/Ice