Answer: 113.04 cubic feet
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Work Shown:
The formula to use to find the volume of a sphere is
V = (4/3)*pi*r^3
In this case, r = 3 is the radius. We'll use the approximation pi = 3.14
This means,
V = (4/3)*pi*r^3
V = (4/3)*3.14*3^3 .... plug in r = 3; pi = 3.14
V = 113.04 ..................use your calculator
The units are in cubic feet. Think of a 1 ft by 1 ft by 1 ft cube block. A sphere can be sub-divided into smaller cubes to get an approximation.