Once all the engineering professors were inside a plane to test how this works out & Before the takeoff a student announced,
"This plane is built by all of your students"
Then all the professors stood up and ran outside fearing for their lives
But the principal was sitting there not moving from his seat . A boy came and asked him,
Boy : Sir Aren't you afraid?
Principal : I trust my students and I know about them well
Principal : I'm sure the plane won't even start