Answer:
i) The density of ice is lower than the density of water. Whenever the temperature dips below 4°C, coldwater begins to expand and become less dense than it should be in order to maintain its original density. Therefore, because cold water is less dense than warm water, it floats to the surface, where it freezes when exposed to the freezing temperatures of the outside environment (which is rare).
(ii) Because ice has a lower density than water, it floats on the surface of the water.