Density : It is a
measurement to
record how
much matter
the object has in
a specific volume
Mode of transportation 1. Hot Air Balloon:
It uses density because the density of
the air decreases density as it gets
hotter, which means it gets lighter and
starts rising up. Hot air balloons use a lot
of heat to keep up in the sky
You'll need to raise the temperature
quite high for the hot air balloon to
raise up, and to land, you have to
decrease the temperature.