The BTU input and output ratings are on the same tag as the model #.
90,000 BTUs - the 090 is what tells you the BTUs of the unit.
80000
Most likely 42,000 BTUs, 3-1/2 tons
4800 BTUs will 150 square feet.
1 gal of #2 fuel oil (or diesel for that matter) has an equivalent of 115,000 BTUS. I say equivalent because it has a little more than that raw (like 136k or so) but the furnace that burns it is only around 85% efficient, therefore you only get 115K BTUS.
A small room is about 5,000 BTUs. Most people don't have a room that would require more than 10,000 BTUs.
trane air handler tonnage for model BWV760P100A1
5,000
A 100 pound propane tank has a capacity of 2,160,509 BTUs
6,520 Btus
A romm 20x9 is 180 square feet. You will need 5000 to 6000 BTUs for this.
The answer depends on the city. Somewhere like Colombo (Sri Lanka) will probably require 0 btus.