Q0) What an odd question and WOW!!! That IS quite a shot. Can you determine the maximum height fo the ball? That WILL reach the cheap seats!
Q1) This is a bit tricky. It just isn't clear who is on which end of the equation. I think the orientation is most logicak if Mr. Lewitt is on his baseline at 0 and Iva's baseline is at 30. This makes the ball land EXACTLY onthe baseline. Hitting the ball at only 29.9, then, requires Iva to stretch to a height of -(29.9)^2 + 29.9(29.9) + 3 = 3 metres. Can this be done? Maybe. In any case, a drop of 2 meters in 14.9 certainly would have the ball land in bounds. Wheter or not this is "safe" remains a question. Does Iva mind if the ball comes back in hsi face?
Q2) Construct ANY parabola where the x-intercepts are the same but the maximum height is significantly LESS thatn 100 meters.