I can honestly say they sleep in high or low temputre
no
Helium (Hydrogen could also be used but this is flamable). Not some balloons are also kept aloft using hot air.
In several big balloons or bladders inside the outer casing.
The best place to purchase mylar balloons in bulk is Party Central. You should be aware that you will not make a large profit from balloons.
You cannot prepare helium balloons too far in advance. You should prepare these balloons hours before the event you need them for.
It should be enough air in the balloons to replace the water weighing more than 150lbs. It should be probably >68 Liters of air. Now you can calculate to distribute 68 liters of air in the balloons. :-)
No, in order for helium to be kept as a liquid it would need to be kept at a temperature of -268.93 degrees celsius.This is both highly difficult, and impracticle, therefore helium is stored and dispensed as a gas.
It should be kept for the life of the individuals involved in the legal matter, in a water and fireproof storage area. It should be kept because it may be needed.
if you do, you may get burned... should a DOG be kept as a "pet"?
should brakes be kept in a good condition
No they should be kept in a hutch or a cage.