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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?

If f(x)= sqrt4x+9+2, which inequality can be used to find the domain of f(x)?

Which describes the difference between the graph of f(x)=x^2 and g(x)=-(x^2-2)