Which phenomenon occurs during the following changes?a). Wax melts in the sun. b). Formation of clouds

a). The phenomenon that occurs when wax melts in the sun is called "Melting". Melting is a process that causes a substance to go from a solid state to a liquid state. It happens when heat is applied to a solid substance like wax, increasing its temperature to a point where its rigid molecular structure breaks down and it becomes a liquid.

b). The formation of clouds is a result of the phenomenon called "Condensation". Condensation is the process by which water vapor in the air is changed into liquid water. It's crucial to the water cycle because it's responsible for the formation of clouds. These clouds may produce precipitation, which is the primary route for water to return to the Earth's surface within the water cycle. Clouds are formed when the invisible water vapor in the air condenses into visible water droplets or ice crystals.