Questions

When you breathe in air through your nose, it contains lots of tiny things, like dust, dirt, germs, and pollen.

The air enters our body through the nose. However, before it enters the lungs, it must be heated and purified. Many dust particles that enter along with the air are removed in the nose by mucus and thus it protects lungs.

Mercedes's language in reference to the story "Call of the Wild" actually means civilization. She had brought numerous belongings along with her and they were much more than the dogs could pull. Her decision of not parting with any of the belongings would ultimately lead to her death. One can easily draw a clear difference between civilization and wildness.

Exercise intensity refers to how much energy is expended while exercising.

The photoelectric effect pointed to the particle properties of light, which had been considered to be a wave phenomenon. Particles like electron and protons have both particle like and wave like behavior. Thus, according to de Broglie, all the material particles in motion possess wave characteristics. Although the dual nature of matter is applicable to all material objects but it is significant for microscopic bodies only.

Testosterone is the hormone which is associated with aggression.