Napkin Rings

A Napkin Ring is made by drilling a cylindical hole of radius r=1in thru a sphere of radius R=2in. Volume is?
If it is drilled through the centre,
volume of sphere minus volume of cylinder
(4/3)(pi)(2in)^3 – (pi)(1in)^2(2 in height) = (>>) 27 cubic inches
this answer is not accurate, but just a rough estimate. I didn’t take into account of volume of cylinder cut away but non existent in sphere
would have to dig out calculus notes to solve this.
solve using triple integrals dV[x^2 + y^2 + z^2]- dV[x^2 + y^2 + z] bounded by intersections.
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