Math
posted by Miracle on .
A rock is placed into a graduated cylinder containing 80 mL of water. What is the volume of the rock if the water level rises to the 120 mL level?

You're kidding.
120 ml  80 ml = 40 ml
Volume of the rock is 40 ml.... 
Well, where did the difference between the final volume and the initial volume come from? Did the water expand,or did something move the water up?

40