An archer releases an arrow from shoulder height of 1.39m. When arrow hits target 18m away, it hits point A (8cm). When the target is removed, arrow lands 45m away. Find the maximum height of the arrow along its parabolic path. Totally lost on this one. Thanks

You may be lost, but please tell us what you've tried. And it would also help to clarify the problem - I don't understand what you mean by "it hits point A (8cm)." Is there a figure that clarifies the height of point A off the ground?