depends on how long you leave it closed.
and if you are referring to Schrodinger cat (felt like I spelled that wrong) the actual question is
if you have a cat in a box for 20 minutes- with a Vial that contained a deadly gas that when spilled over kills the cat.
So after the 20 minutes, will the cat be dead or alive.
The answer is:
Both, but at the same time neither.
you can never know until you open the box