How much potassium sorbate and Camden tablets for a gallon of mead?

I've been searching Google and watching videos for the past half hour and can't find this anywhere, somehow. I have one gallon of mead, a bag of potassium sorbate, and some 550mg Camden tablets.

How much do I need to add to stabilize this? 1 whole tablet? Half a tablet? 1 tsp of potassium sorbate? A tablespoon?