1/4 divided by 1/2 in simplest form

The volume of gas a balloon can hold varies directly as the cube of its radius. imagine a balloon with a radius of 3 inches can hold 81 cubic inches of gas. how many cubic inches of gas must be released to reduce the radius down to 2 inches?

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Select the point that is a solution to the system of inequalities. y< =-x+3 y=x^(2)-3x