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King
A baseball player hits a homerun, and the ball lands in the left field seats, which is 120 m away from the point at which the ball was hit. The ball lands with a velocity of 20 m/s at an angle of 30 degrees below horizontal. Ignoring air resistance (A) find the initial velocity and the angle above horizontal with which the ball leaves the bat; (B) find the height of the ball relatively to the ground
I believe that you are not stating the question completely. You haven't enough information. Is (B) asking the height of the ball relative to the ground when it hits the seat 120 m away, or the maximum height the ball attains on its flight to that seat. Also, is the seat at ground level, or is it some number of rows up... I think you need the height at which the ball lands in the seat and quite possibly the height at which the ball was initially struck.