It takes ____ breaths for an inhaled volume of air to travel through a ____ respiratory system.

A) two; bird's
B) one; bird's
C) three; amphibian's
D) two; amphibian's
E) two; fish's

Respiratory System

The network of organs and tissues that help you breathe, including the lungs, airways, and muscles.

Amphibian's

Vertebrates that can live both in water (using gills) and on land (using lungs), including frogs, salamanders, and newts.