Answer: 88 feet.
Step-by-step explanation: For this problem, to find the elevation of the top floor we will simply subtract 36 feet from 124 feet, or we could add -36 feet to 124 feet.
124 + (-36) Is like subtracting 124 - 36.
So, 124 + (-36) = 88
This means that the elevation of the top floor is 88 feet.