The actual height of building is 1800 feet.
Step-by-step explanation:
Given,
Height of building in model = 3 inches
Scale used by engineer;
1 inch = 600 feet
Therefore;
Actual height of building = Height in model * Scale used
Actual height of building = 3 * 600
Actual height of building = 1800 feet
The actual height of building is 1800 feet.