Q:

If the angle of elevation of the sun changes from 30^o to 45^o then length of the shadow of a pillar decreases by 20 meters. The height of the pillar is:

• 1
  $$ {20(\sqrt{3}-1)}\ meter$$
• 2
  $$ {20(\sqrt{3}+1)}\ meter$$
• 3
  $$ {10(\sqrt{3}-1)}\ meter$$
• 4
  $$ {10(\sqrt{3}+1)}\ meter$$