Wilbur landed his plane.
The plane's elevation relative to the ground (in meters) as a function of time (in seconds) is graphed.
![graph](web+graphie://ka-perseus-graphie.s3.amazonaws.com/8f82893c0aeefca4f9ded741387c938b5994363f)
**How long did it take the plane to land?**
[[☃ numeric-input 1]] seconds