VMany technologies use enclosed fluids. For example, a hydraulic press at an auto repair shop uses trapped water to lift heavy cars. Hot-air balloons heat trapped air to lift a basketful of people. Look at the two diagrams that model fluid particles. •The first cup A has many tightly packed circles. •The second cup B has fewer and more widely spaced circles in motion.

A classroom thermometer contains alcohol in a very thin tube. The liquid rises in the tube as the temperature rises. This happens because the liquid particles spread out as they warm. Why do thermometers use a liquid instead of a solid or a gas? Use evidence from the diagrams to support your answer.