how does a jet get off the ground
Given a skilled enough pilot - yes.
ground
Gravity.
Gravity.
Rockets are launched from the ground, while the space shuttle is launched off the back of a jumbo jet.
The pilot. All the mechanical parts on the plane are important, but if a pilot doesn't start the engines, taxi to the runway and open the throttles, the plane won't lift off the ground.
The best way is with a hard jet of water from a hose. Knock them loose physically by washing them off the plant. Once they hit the ground, they cannot climb back up.
At higher elevation, and colder temperatures, airplanes require more runway to lift off the ground. It's the contrary for warm temperatures.
The answer will be different for every jet based on multiple factors; the weather, the speed of the jet at take-off, the angle in which the jet is ascending and the size/weight of the jet and items or people in the jet. Most commercial planes will not fly more than 7-8 miles above ground due to the thin atmosphere not being able to support the jet. Depending on the situation, between 5-8 miles above the house would be a solid estimate.
The Harrier Jet also known as the "Jump Jet" takes off vertically.
No
The Harrier is used by the marines and is an attack and ground support Aircraft. This aricraft is also a VSTOL (Verticle Short Take Off and Landing)