yes
Of course milk needs to be refrigerated because if you don't refrigerate it, it will get chunky and go bad.
As long as it stays refrigerated, it should not go bad before the expiration date. If it's left out, it should be eaten the same day. Depending on tempertaures, you could go another day, but I personally wouldn't.
yes after a while. if you want it to last longerput it in the freezer
No, unless mixed, than it needs refrigerated.
Blackberries do need to be refrigerated, or else they will go bad
All penicillin will go bad after a period of time, but it is actually better to keep liquid penicillin refrigerated. It is a good idea to check the expiration date on your penicillin, and dispose of it when it expires. Penicillin that has gone bad will not help you, and you should be careful with medications that are past their date.
Yes it can spoil with out refrigerated.
If it smells bad. You'll know.
Yes. It will become moldy if not eaten within a week or so.
It can be any part of it or several of the ingredients that go into gravy.
The smell