From two points P and Q on the same side of a tower in a straight line with its foot, Q being 20m nearer the tower than P, the angles of elevation of the top are 30∘ and 45∘ respectively. Find the height of the tower (nearest tenth).
a) 30.0 m
b) 27.3 m
c) 34.6 m
d) 20.0 m