18. The density of ice is less than the density of water because... the molecules in ice are well the mass of ice molecules less A arranged. B than the mass of water molecules. the forces between ice the molecular separation in ice C molecules are weaker than that D is larger than in water. in water. 19. Water can exist as solid, liquid and gas when it is at A melting point B boiling point C absolute zero D triple point 20. Y is a steel wire of length I and has a diameter of 2d. Z is another steel wire of length 21 and diameter 2d. A load of weight W hangs from the lower end of each wire. Which of the following is the ratio of the strain in wire Y to that wire Z? A 0.5 B C 4 D