Explain how the sense of smell works on a molecular level. Be sure to describe what is happening in the brain as well?

The smell is one of the senses that is created by the small molecules that are released by the food, aromatic substance, or any substance into the air. When we inhale during the breathing process these small molecules enter our nose and trap in tiny hair of the nose.

These molecules dissolves in mucus present in the nose to reach the specialized receptor cells known as olfactory receptor neurons. These neurons detect the smells and send the information directly to the brain to the olfactory bulbs that work to detect the smell.

the answer is b: 1.4 km/hr