I'm probably too late with this comment ... but if the diameter of the tube is significantly larger than the diameter of the ball, and the initial velocity of t

I'm probably too late with this comment ... but if the diameter of the tube is significantly larger than the diameter of the ball, and the initial velocity of the ball is large enough, then the trajectory of the ball as it leaves the "curved tube" won't necessarily correlate well with the straightforward textbook answer you'd expect to see. Perhaps the original context for the question made this a bit more clear, but as presented in the article, the "real world" might intervene.