Question

Choose the correct statement from the options given below:

• A. The atmosphere is divided into 4 layers.
• B. Oxygen level above 15% in the atmosphere does not support fire.
• C. Oxygen level above 25% in the atmosphere causes fires which are impossible to put out.
• D. The air which we breathe in consists of 16% oxygen by volume.

Answer 1

The correct option is C Oxygen level above 25% in the atmosphere causes fires which are impossible to put out.

• The air which we breathe in consists of 21% oxygen by volume and the air which we breathe out consists of 16% oxygen by volume.
• The atmosphere is divided into five layers: troposphere, stratosphere, mesosphere, ionosphere and exosphere.
• The oxygen level below 15% in the atmosphere does not support fire.
• The oxygen level above 25% would cause forest fires and other types of fires which are impossible to put out