A building has eight levels above ground and one level below ground. The height of each level from floor to ceiling is feet. What is the net change in elevation going from the floor of the underground level to the ceiling of the fourth level above ground? Assume the floor at ground level is at an elevation of zero feet.

72.5 feet

Step-by-step explanation:

The height of each level from floor to ceiling is 14 1/2 feet.

We want to find the net change in elevation going from the floor of the underground level to the ceiling of the 4th level above ground.

In other words, the change in elevation in going 5 floors up.

Each level has a height of 14 1/2 feet (29/2 feet).

Therefore, the height of the fourth level above ground from the underground level will be 5 times the height of one level:

h = 5 * 29/2 = 72.5 feet

The net change in elevation from the floor of the underground level to the 4th level above ground is:

ΔE =

Therefore:

ΔE = 72.5 - 0 = 72.5 feet