Answer: 24 feet
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Explanation:
Assume the ground is completely flat and level. We have a right triangle with hypotenuse 30, and the horizontal base leg is 18. The vertical leg is unknown, so we'll call it x.
Use the pythagorean theorem to solve for x
a^2+b^2 = c^2
x^2+18^2 = 30^2
x^2 + 324 = 900
x^2 = 900 - 324
x^2 = 576
x = sqrt(576)
x = 24
The height of the tower's floor is 24 feet.
