William is walking straight across a field towards a vertical flagpole. He observes that when he is at point A ,the angle of elevation of T, the top of the flagpole , is 30degrees and when he is at point B ,on the same side of the flagpole as A ,the angle of elevation of T is 44 degrees .The distance between A and B is 20 metres a. Using a scale of 1cm to represent ,4m construct a single diagram to show the relative positions of A ,Band T . b. Using a suitable construction on the same diagram ,find the height of the flagpole