Question 54041
Think of this:
The shadow makes a leg of a triangle. The height of the mast makes the other leg.
Adj. leg ~> 20
Opp. leg ~> 35
Tan( angle of elevation ) = opp. / adj. = 35/20 = 7/4
angle of elevation = cot( 7/4 ) or about 60.255118....
Angle of elevation is roughly 60 degrees.