Answer:
C
Step-by-step explanation:
what happens, when you rotate something around a pole ? what shape is the most outside point making around that pole ?
a circle, of course.
that means rotating the rectangle around the x-axis creates a round object (with the bottom area being a circle).
so, all answers about a prism (rectangular bottom shape) are automatically wrong.
again, just imagine to rotate a small sheet of paper around a pole (the x-axis acts like one in this scenario).
the result is a solid with a circular bottom area, and it maintains this shape all the way to the top.
it is a cylinder !
and what is its radius ?
well, the outermost point of the rectangle is 8 points away from the x-axis. when we rotate this rectangle, that attribute remains, of course. and every point on the side surface of the resulting cylinder has the same distance from the central x-axis : 8.
so, the radius is 8.
and the volume of a cylinder is
ground area × height = pi×r² × height
in our case
pi×8² × 5 (the width or "height" of the rectangle) = pi×64 × 5 = 320×pi
