Dead air space acts as an insulator.
Most air purifiers contian "media" that can reduce odors and chemicas from the air.
Our coutry pakistan is growing trees to reduce air pollution
Unleaded petrol was introduced to reduce lead pollution of the air.
Oil is mainly used to reduce friction between contacting surface, e.g., metal on metal - not to reduce air friction.
As you should know, the purpose of insulation is to create dead air space. DEAD air does not transfer temperatures.
by flying in the air
How does the flow of air reduce friction of the hovercraft in motion?
The air pressure would reduce.
You don't "resist" it but you "reduce" it. For example, many vehicles and projectiles are made in a streamline design to reduce air resistance.
Dead Air for Radios was created on 1998-06-08.
during flight aircraft reduce speed by spoiler