• True or false statements:

      1. A liquid will sink when it is hotter than the liquid around it. False

      2. Thermal convection happens in liquids and gases. True

      3. Thermal convection happens in solids. False

      4. Sea breeze is caused by thermal conduction. False

      5. Tea at the top of a cup is hotter than tea at the bottom of the same cup. True

• Hot-air balloon rises because the hot air inside it is less dense than the cool

        air surrounding it.