Emir is standing in a treehouse and looking down at a swing set in the yard next door. The angle of depression from Emir's eyeline to the swing set is 33.69°, and Emir is 10 feet from the ground. How many feet is the base of the tree from the swing set? Round your answer to the nearest foot.
a) 15 feet
b) 18 feet
c) 20 feet
d) 24 feet
