In the diagram, which represents the roof of a house, \(ABCD\) is a horizontal rectangle and \(XY\) a line parallel to \(AB\) and \(DC\). \(AB=40'\), \(BC=XY=16'\) and \(AX=BY=CY=DX=17'\). Calculate \((i)\) the height of \(XY\) above the plane \(ABCD\), \((ii)\) the angle of inclination to the horizontal of the face \(AXYB\), and \((iii)\) the angle of inclination to the horizontal of the edge \(AX\).