Usually in the wings.
Boeing Commercial Airplanes was created in 1916.
Boeing Commercial Airplanes's population is 60,000.
Gas turbine engines have less moving parts,so they last longer.They run on kerosene which is cheaper.This is the simple answer.
Yes, but not commercial airplanes.
Bathrooms
Airplanes are not made of gas.
The most popular commercial airplane is the Boeing 737.
Hundreds of thousands! (approx.)
Stratosphere
Countless.
Yes, they can run out of gas.
Because in most commercial airplanes, you would not be able to open any exit in order to jump out.