Solve the Problem $\mathrm { d } \mathrm { ft }$

Solve the problem.
-It can be shown that if the angle of elevation from an observer to the top of an object is A and the angle of elevation $\mathrm { d } \mathrm { ft }$ closer is $\mathrm { B }$ , then the height of the object is given by $h = \frac { d } { \cot A - \cot B } f t$ .
Find $\mathrm { A }$ if $\mathrm { h } = 80 \mathrm { ft } , \mathrm { d } = 50 \mathrm { ft }$ , and $\mathrm { B } = 28 ^ { \circ }$ . Give your answer in degrees to the nearest hundredth.

A) $21.76 ^ { \circ }$
B) $19.25 ^ { \circ }$
C) $26.51 ^ { \circ }$
D) $24.18 ^ { \circ }$