how to find the volume ?

[molten ridge]

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[dawn badge]

draw perpendiculars to AB through D and C, let's call the intersections to AB: P and Q
now DCPQ is a rectangle, if you rotate that around AB, you get a cylinder. and the triangles rotated give you a cone. the cylinder is super easy, for the cones you have to find their hights (AP and QB)

but AP and QB is also doable with a little bit of pythagoras

[molten ridge]

u can use volume of frustum formula