Explanation:
Heat transfer by convection involves gases and liquids as a result of density differences when they are heated.
In the hot air balloon, the air closer to the heater is warmed. This air becomes lighter and it rises. This in turn pushes the balloon up. The cold air away from the heater is denser and begins to sink.
This exchange of hot and cold air sets up convection cells within the balloon and this how heat transfer is attained.
Answer:
A. reducing the amount of time it takes to travel between countries.
Explanation:
A sea is great body of water, usually salty, that covers the earth broadly. It is a connected body of salt water that covers 70% of the earth.
The ocean on the other hand, is a large area of water in between continents. They are very big and they join smaller seas together. Together, the oceans are like one "ocean", since all the "oceans" are joined
