To remove polluted air from room we use what type of fan?

When we inhale dust we may catch cold and sneeze what is the name of this condition?

Carbon-monoxide mixes with hemoglobin which in our blood and produces

How many percentage of nitrogen present in the air?

After the industrial revolution in Britain the white moth changes into which colour?

If ozone layer will damage what will happen?

Solar energy take from which source?

Write an example for smoke producing things?

If we place a sheet of white paper just above the flame for a second. What happened to the paper?

What is the short form of Chloro-Flouro-Carbon?