Answer :
The reading at finished grade would be 1.5 feet.
To determine the reading at finished grade, you need to subtract the difference in elevation between the benchmark and finished grade from the initial site reading at the benchmark. In this case, the benchmark is at an elevation of 100 feet and the finish grade is set at 97 feet, which means there is a difference of 3 feet in elevation.
Given that the site reading at the benchmark is 4.5 feet, you need to subtract the 3 feet difference in elevation.
Therefore, your reading at finished grade would be 4.5 feet - 3 feet = 1.5 feet.
In conclusion, the reading at finished grade would be 1.5 feet.
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