The exact amount of time varies on the environment it's left in, though the first signs of bad beef is an odd discoloration and a rancid smell.
You should use beef stock two weeks after opening.
Beef is not bad for your system in small amounts. You will also not want to eat beef that is not properly cooked.
Maybe not. It depends what made the beef "bad".
the word "un" in that word unfrozen is a prefix
Not necessarily, browning of beef while in the freezer or fridge just means that it is not as fresh as it could be. If it has a green tinge to it you know it is now bad.
If beef taste like fish then throw it out.
Yes, it is. You should not eat bad beef because it causes potentially fatal food-borne illness.
Frozen batteries last longer unfrozen batteries.
As long as it doesn't smell bad you can eat it, as long as it has been fully frozen it will not go bad (Though it might dry out a bit)
look at the label
As the frozen cupcakes will require extra time to defrost, the unfrozen cupcakes will bake faster.
No