Just an odd thought.
One could have a decent static rope as a stern line in a bag. Say a 100 footer while there was a 50 foot bow line. Everything quickly connected by 'biners.
This stern line could also find itself useful as a ridge pole line for a tarp over the kitchen as needed.
Why I mention it here is say you can only afford, (weight and price), a 100 - 150 ft static line in your rescue throw kit.
This added stern line from the tree to the pulley wouldn't need to be as strong as the main line, if one used the 5:1 system described by Avatard.
Go to the 5:00 mark for the explanation in the above video on post 41.
Having this added stern line means you wouldn't have to raid the bow line on your boat.
Now lets say you wanted a really effective way to throw your rope in that rescue kit.
I noticed when setting up the floats on my crab pots how easy it would be to throw a rope by doing a David slinging motion with a weight on the end. Having that weight a floating device on a floating rope makes sense.