volume to be
V π · 8^2 · 25 + π · 6^2 · 25 + π · 4^2 · 25 + π · 3^2 · 25.(A)(C) H′(3) = f ′ (g(3)) · g′(3)= f ′(2) · g′(3).(E) M′(3) = f (3) · g′(3) + g(3) · f ′(3) = 4 · 3 + 2 · 2.(E)(C)(D) Here are the pertinent curves, with d denoting the depth of the water: