Sam sees a UFO hovering in the sky. He measures the angle of elevation of the UFO at 30 0. He calls Julie, who is 15 miles closer to the UFO and asks her what her angle of elevation to the UFO is. She measures it to be 55 0. The alien in the UFO sees the two kids and flies to a point directly over Julie's head (same altitude). This flight takes exactly one minute. How fast did the UFO move in miles per hour?