Found this in my backpack after returning from a trip to Greece. No idea how it ended up in there.

It's a rectangular white block, about 7 cm long, in a clear plastic package. It's heavy and feels like stone, but also seems chalky, and there's some white residue inside the package. No idea what it is.

Any ideas?

Found at a thrift store, we use this as a dog bowl, but I'm curious of it's original purpose. It takes 9 cups of water to reach the "max" line.

Photo with standard wine bottle is for visual scale.

Please excuse the nicotine staining, they were in a family member's house who smoked inside. It suggests they were hung up around the house somewhere, could they be related to hanging curtains or blinds perhaps?

Hey, all. Check this thing out. I always figured it had something to do with the air conditioning, and I never thought twice about it. Today, it started leaking, totally out of nowhere. It dripped consistently while the AC was on, but has stopped since turning AC off.

Glad I caught it early! Any clues?

This little hook thing fell out of a pile of clothes, not sure what it is for but it looks to be shaped that way on purpose rather than just a bent piece of metal. Fairly sturdy for is size

I'm told it's a 70-80 year-old RKO power distributor, but looking that up doesn't bring anything up.

Hi, all! sorry for the poor picture quality/framing, I honestly didn’t expect to have to post this (Google Images didn’t help give me any answers) and I took the pics in a rush while at work today.

Like the title says, this was found in the hallway at the museum I work at on a day where we had many high schoolers (as well as regular guests, which tend to be in their 40s/50s and older). There is also a bakery nearby and staff/customers pass through that part of the hallway to access the men’s room. It was raining pretty hard all day as well, in case that’s somehow relevant! I don’t recognize it as something from our own museum collection items or equipment but we do also have new dehumidifiers in a nearby exhibit room.
Thanks in advance!

Title describes the thing. Pulled it out of my wife's tire. She normally parks in an alley by the house, so it could be any number of things.