A remote-controlled toy helicopter is hovering at a fixed height above the ground when it loses contact with its remote control. As the helicopter begins falling, a wind picks up that causes it to follow the trajectory r(t) = ti 3tj + (10-5t)k, where t is the time since it started falling (in seconds), r is in meters, and k is up. 1. How far above the ground was the helicopter initially hovering? 2. When does the helicopter crash into the ground? 3. At what angle (from the ground) does the helicopter crash into the ground?