500sq.ft
A romm 20x9 is 180 square feet. You will need 5000 to 6000 BTUs for this.
You cannot. There are infinitely many combinations for the sides of a room that will yield an area of 5000 square feet even after you simplify the problem and assume that the room is rectangular in shape. Suppose the room is L feet long where L > sqrt(5000). Then let W = 5000/L feet. The area of the room, which is L feet long and W feet wide, is L*W = L*(5000/L) = 5000 square feet. That is true whatever the value of L. And since L can have any value greater than approx 70.71 feet, there are infinitely many possibilities.
5000 BTU's should work for a room that size.
You should cool food down at least to room temp before freezing.The faster you cool cooked food the less likely bacteria will have to form on it. Putting it in an ice bath is the correct way to cool food before refrigerating or freezing it.
you should store them in cool dry room temperature place
You should let it cool completely to room temperature before wrapping. Otherwise, moisture will form between the wrapping and the bread which will make it soggy or sticky to the touch.
No, if you are not in the room you are just wasting electricity.
AFU
A 4000 btu should do it.
5000 BTU is a tiny amount of cooling - are you sure you don't mean 50,000 BTU? A 5000 BTU might give you a drop of 5 degrees C in a 6' x 8' office with no south facing windows, as long as the ceiling isn't too high. For a normal 10' square room, 12,000 BTU is a more reasonable starting point, then add more for sources of heat gain in the room.
No. Serve it at cool room temperature.
you will probably will require 10 AC 5000 sq feet room