Acone has a diameter of 18 units and height of 8 units. what is its volume?

the radius of your cone is half of 18 units = 9 units.

the volume of any cone is      v = (1/3) · (pi) · (radius)² · (height)

-- take that formula for the volume of any cone.
-- write '8' in place of 'height'.
-- write '9' in place of 'radius'.
-- write '3.142' in place of 'pi'.
-- complete the arithmetic.
-- bada-bing, you've got the volume.

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