See the attached diagram.
In the right triangle, x is opposite the 23.6 degree angle, and the adjacent side is 250 m. This suggests using the tangent ratio.

Finally, to get the height of the tree, add Sarah's height, 1.5 m.
The tree is approximately 110.7m tall.
I'm sorry I'm not home so I can't tell you the answer to this but what I can tell you is put together the xy and then put together the -13-20. Hope this helps.
14+7= 21
8 x 21=168
8 x 7= 56
224
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