The height of bottom of mirror = 6m,
Height of top of pole = 4m,
Distance between pole and mirror = 2m
Viewing distance from mirror = 4 + 2 = 6m and viewing distance from pole = 4 m
Maximum height up to a man at a distance of 4 m can see the top of the pole = 6+2+8 = 16 m
minimum height up to person can see the pole = 6 + 4 = 10 m