Final answer:
The width of the river across a canyon can be calculated using trigonometry and surveyor's measurements.
Explanation:
The width of the river can be calculated using trigonometry based on the surveyor's measurements.
By using the angle and the distance walked along the river as a baseline, the width of the river can be determined.
In this case, the width of the river would be approximately 117 feet.
Learn more about calculating width of a river using trigonometry here:
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