Question

*Geometry, i know how to do it but the answer i come up with doesn't match.

Two birds sit at the top of two different trees 17.8 feet away from one another. The distance between the first bird and a bird watcher on the ground is 37.4 feet.

*I know you must use the cos option on your calculator and i divided 17.8 by 37.4 like the formula says but still no matching answer..

What is the angle measure, or angle of depression, between this bird and the bird watcher?
25.5°
28.4°
61.6°
64.5°

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