An aeroplane flies horizontally due east at a constant speed of 240km/h. From a point P on the ground, the bearing of the plane at one instant is 311 degrees true north and 3 min later the bearing of the plane is 73 degrees T whilst its elevation then is 21 degrees. If h metres is the altitude of the plane, show that h=12000 sin 41 tan 21 cosec 58 and calculate h to the nearest metre.

If a is the angle of elevation of the areoplane at the first point of observation, show that tana = sin 41 tan21 cosec17 and find a to the nearest minute

DIAGRAM IS ATTACHEDDD

(not 100% sure diagram is correct but relatively sure)

PLEASE HELPPPP !!!!!

thankyouuu !!