angle of depression is the angle that is created below the horizontal with your line of sight. to solve the angle of depression, use the formula:
tan(d) = o / a
where d is the angle of depresion
h is the opposite side of the angle which is the height 60 ft
a is the adjacent side of the angle which is 25 ft
tan( d ) = 60 / 25
d = arctan ( 60 / 25)
d = 67.38 degrees