Pole A, whose coordinates are 20 degree N, 50 degree E, is to be rotated about the axes described below. In each case, find the coordinates of the final position of pole A and show the path traced out during its rotation.
a) 100 degree rotation about the NS axis, counterclockwise looking from N to S.
b) 60 degree rotation about an axis normal to the plane of projection, clockwise to the observer.
c) 60 degree rotation about an inclined axis B, whose coordinates are 10 degree S, 30 degree W, clockwise to the observer.