On a cloudy day yong sun needed to know the height of a window in a building. Yong sun positioned a mirror on the ground between herself and the building so that when she looked in the mirror she saw

On a cloudy day yong sun needed to know the height of a window in a building. Yong sun positioned a mirror on the ground between herself and the building so that when she looked in the mirror she saw the window.if the mirror was 21.9cm from her feet and 30.98m from the base of the building and yong suns eye was 1.8m above the ground how high up on the building was the window located