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The volume of a sphere is `V=4/3pir^3` , so the volume of half a sphere is `V=2/3pir^3` .
To find the volume of the hemisphere with radius 3 inches, substitute the value into the formula and simplify
`V=2/3 pi r^3` sub in r=3
`=2/3pi 3^3` cancel common factor of 3
`=2pi 3^2` simplify
The volume of the hemisphere is `V=18pi` cubic inches.