Let's call the height of the building "h". We can use the tangent function to relate the angle of elevation to the height of the building:
tan(30°) = h / (42 + 5)
We add 5 to the distance of 42 feet, because Ana's eyes are 5 feet above the ground. We can simplify this equation by evaluating the tangent of 30 degrees:
1/√3 = h / 47
To solve for h, we can multiply both sides by 47:
h = 47/√3 ≈ 27.17 feet
So the height of the building is approximately 27.17 feet. Rounded to the nearest hundredth foot, the height is 27.17 feet.