Part A At what temperature do the combined effects of contraction and expansion produce the smallest volume for water? \( -100^{\circ} \mathrm{C} \) \( 4^{\circ} \mathrm{C} \) \( 0^{\circ} \mathrm{C} \) \( -4^{\circ} \mathrm{C} \)

Did you know that water is most dense at \( 4^{\circ} \mathrm{C} \)? This temperature is a unique point where the combined effects of thermal expansion and contraction create the smallest volume for water. Below this temperature, water begins to expand, which is why ice floats—a phenomenon that has critical implications for aquatic life! Interestingly, this property of water affects our climate and environment significantly. For example, when lakes freeze, the ice forms at the surface, insulating the water below and allowing fish and other organisms to survive the harsh winter months. It's one of nature's fascinating quirks!