C) floatation
Floatation<span> is a separation process in which </span>minerals<span> that are valuable are separated from worthless material or other valuable </span>minerals<span> by inducing them to gather in and on the surface of a froth layer</span>
I would go with A : weathering and erosion
I was going to say C : volcanoes and earthquakes but when you read the pictures it says “ Mountains , low hills & rolling plains “
I think the EAR is 7.79%
Since EAR = e^0.75 -1
= 7.79%
