Answer:
hot-air balloons
Explanation:
More recently, aerial photographs have often been taken from fixed-wing aircraft and today can even be taken from unmanned aerial vehicles (also knowns as drones).
Streak, color, luster, crystal structure.
The correct answer is - ozone.
The ozone is essentially three molecules of oxygen, or O³. This gas is crucial for the life on the Earth because it is the one that manages to filter out big portion of the UV radiation from the Sun which is extremely harmful if its too strong, as it will contribute to the dying out of pretty much every living organism.
While the ozone layer in the stratosphere is very useful, the ozone in the lower parts of the troposphere is actually considered as pollutant. The reason why it is considered as pollutant is because it is very harmful if inhaled, and it also heavily damages the plants.
Answer:
External/ internal migration.