Answer:
about 80.03 feet
Explanation:
You want the change in height of a bridge with a span of 1068.5 feet and a grade of 7.49%.
Grade
The grade of a roadway is the ratio of rise to run:
grade = rise/run
7.49% = rise/(1068.5 ft)
Solving for the rise, we have ...
rise = (1068.5 ft)(0.0749) ≈ 80.03 ft
The height change is about 80.03 feet.
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Additional comment
Your problem statement tells you to round this value. We cannot see what precision it is asking for, so you'll have to figure the rounded value yourself. The attachment shows the value you'll be rounding.