The surface elevation of Lake Powell is decreasing at the rate of 77.2 feet per year.
<h3>What is the rate(slope) at which the sea is decreasing?</h3>
The rate at which the surface elevation of the Lake Powell is decreasing can be determined by calculating the slope(steepness) of the sea.
The slope can be given as:
Slope (Δm) = rise/run
Slope (Δm) = Δy/Δx
slope (Δm) = y₂ - y₁/x₂-x₁
slope (Δm) = 3263.4 - 3881/2006-1998
slope (Δm) = -617.6/8
slope (Δm) = -77.2
Therefore, we can conclude that the surface elevation of Lake Powell is decreasing at the rate of 77.2 feet per year.
Learn more about calculating the slope here:
brainly.com/question/1884491
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