Question 3 Example 4.22. The angle of elevation from a boat at P to a point T, at the top of a vertical cliff is measured to be 30°. The boat

sails 1000 metres to a second point Q, from which the angle of elevation to T is measured to be 45°. Let R be the point at the base of the cliff directly below 7 and let h be the height of this cliff. The bearings of R from P and Q are 050ºT and 310ºT respectively. a) Draw a diagram expressing all this information. b) Show that ZPRQ = 100°. 1000² c) Show that h²= 4+2√3 sin 10° d) Hence evaluate the height of the cliff correct to the nearest metre.