Question 1177411
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<pre>

Let x be the distance to the plateau.


Then we have  


    tan(20°) = {{{40/x}}}.


But  tan(20°) = 0.3638;  therefore


    40/x = 0.3638


which implies


    x = 40/0.3638 =  109.96 meters = 110 meters (rounded).    <U>ANSWER</U>
</pre>

Solved.