Answer:
The time span between 1680 and 1766 (lines 1 and 2) is 86 years: 1766 − 1680 = 86 years. During this time, the falls receded an average of 5.8 feet per year: 500 feet ÷ 86 years ≈ 5.8 feet per year.
The time span between 1856 and 1876 (lines 3 and 4) is 20 years: 1876 − 1856 = 20 years. During this time, the falls receded an average of 25 feet per year: 500 feet ÷ 20 years = 25 feet per year.
Explanation:
plato answer ^
John Tuzo Wilson developed crucial concepts that related to plate tectonics in 1963.
He asserted that the Hawaiian, and other island chains, may have formed due to movement of a plate over a "hot spot" in the Earth's mantle.
[Note: A __Hotspot___ is an area of abnormally intense active volcanism.]
He also argued that there must be a third type of plate boundary to connect ridges and trenches- which are called transform faults. These allowed for plates to slide past one another without oceanic crust being created or destroyed.
I think the answer is C <span>moderate </span>
