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Boeing Commercial Airplanes was created in 1916.
Boeing Commercial Airplanes's population is 60,000.
Yes, but not commercial airplanes.
The most popular commercial airplane is the Boeing 737.
Hundreds of thousands! (approx.)
Countless.
Stratosphere
Usually in the wings.
Because in most commercial airplanes, you would not be able to open any exit in order to jump out.
Only the captain,his word is LAW
Of course! Remember reading about the Wright Brothers? They made the first documented flight in a powered airframe on Dec. 17th, 1903. WWI saw airplanes play a significant role in combat so by 1919 they were well established.
Depends on your definition and what kind of airplane. Large commercial airplanes are the most efficient way to move people. Small airplanes are horrible wastefull things.