After the second, it will be 50, after the third it will be 20, and after the fourth it will be 8. The answer is C
Hope this helps!
V=hπr^2
V=(2k+1)π(3k)^2
V=π(2k+1)(9k^2)
V=π(18k^3+9k^2)
V=18πk^3+9πk^2
a)
the average speed, well it does 10 ft in 1.6 secs, so is simply their quotient, 10/1.6 = 6.25 ft/s on average.
b)
over the horizontal, well, it covered horizontally 9.25 ft in those 1.6 secs, so their quotient is 9.25/1.6 = 5.78125 ft/s on average.
c)
we don't know the vertical distance, but

so, it covered vertically about 3.8 ft in those 1.6 secs, so then 3.8/1.6 = 2.375 ft/s on average
Area of sector = (1/2) * r^2 * α where α = the angle in radians
= 1/2 * 12^2 * π/3
= 72 π / 3 = 24 π Answer