I believe it would be B but I'm not 100% sure. Like i warn everyone, TRUST SOMEONE ELSE BEFORE TRUSTING ME. I would hate to see you get the wrong answer cause of me...
If the height of the building is 100 ft, and the angle made with the ground is 30°: You can say that tan(30) = 100/x Rearranging for x you get x = 173.2 ft
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