Which algebraic expression represents “the difference of 54 and a number”? HELP I AM TIMED ASAP

Hurry and answer this! circle x with a radius of 6 units and circle y with a radius of 2 units are shown which steps would prove the circles similar? translate the circles so they share a common center point, and dilate circle y by a scale factor of 4. translate the circles so the center of one circle rests on the edge of the other circle, and dilate circle y by a scale factor of 4. translate the circles so they share a common center point, and dilate circle y by a scale factor of 3. translate the circles so the center of one circle rests on the edge of the other circle, and dilate circle y by a scale factor of 3

What is the unit rate of, 75% high fiber chimp food to 25% high protein chimp food.

What is the ratio fraction form of 25: 9