If on a scale drawing 25 feet are represented by 15 inches then a scale of 1/15 inche represents how many feets

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?

With number 11 ( show how you got the answer)

Will mark name all segments skew to bc