Hot air is less dense than cool air, so hot air will rise above cool air. Increasing the air temperature inside a hot air balloo
n makes it lighter than the surrounding air, so the balloon can lift up. The density of hot air is about 0.25kg/m^3 less than that of cool air, which means a cubic meter of hot air can lift about 0.25kg. What is the minimum volume of hot air needed to lift a hot air balloon carrying
Step-by-step explanation: since 7+3 is in paranthases you add them first to get 10 and you multiply it by the 3 to get 30. We know its correct because 21+9=30.
