The answer is: " 128π in³ " .
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Note: The formula/equation for the volume of a cylinder is:
V = Base area * height.
The base area is a circle: A = π r² ; r= radius;
So , the formula/ equation for the volume of a cylinder is:
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V = π r² * h ; (h = "height").
Given: r = radius = 4 in. (given) ;
r² = (4 in.)² = (4 in.)*(4 in.) = 16 in.² .
h = height = 8 in. (given).
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V = π r² * h ;
V = π * 16 in² * 8 in. ;
V = π * 128 * in² * in. ;
V = 128 π in³ .
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