Cylinder Volume = ¼ • π • d² • height
12,464.27 = .25 * PI * 23^2 * height
height = 12,464.27 / .25 * PI * 23^2
height = 12,464.27 / .25 * PI * 529
height = 12,464.27 / 415.4756284373
height = 30 mm
The vertical cross-section would be 23 mm * 30 mm =
690 SQUARE millimeters (NOT cubed as the answer says).
answer is C