AB is a vertical pole. The end A is on the ground level. C is the middle point of AB and P is a point on the ground level. The portion BC subtends an angle at P. If AP = nAB, then is equal to
None of these
From a point on the level ground, the angle of elevation of top of a pole is on moving 20metres nearer,the angle of elevation is . Then,the height of the pole , is
15
20
If the axes are rotated through an angle 45° in the positive direction without changing the origin,then the co-ordinates of the point (, 4) in the old system are
0
D.