Question 1198992
 the top diameter of the reservoir must be 50m.
 The depth of the reservoir is indicated at 30m.
:
I. What volume of water can be stored in the reservoir?
the volume of a cone: V = {{{1/3}}}*{{{pi*r^2*h}}}
radius is half the diameter: 25m
V = {{{1/3}}}*{{{pi*25^2*30}}}
V = 19635 cubic meters
:
II. What is the surface area of the wall of the cone?
Surface area of a cone. SA = {{{pi*r*L}}}, where L is the slant height
Find the slant height which is the hypotenuse of a triangle formed by the radius and the height
L = {{{sqrt(25^2 + 30^2)}}}
L = 39 meters
then
SA = {{{pi*25*39}}}
SA = 3067 sq meters