The structures of the upper respiratory system include the lungs.
are located inside the thorax.
allow gases to enter and escape the body.
allow for movement of gases in and out of cells.

Include the lungs.

Explanation:

The upper respiratory system, or upper respiratory tract, consists of the nose and nasal cavity, the pharynx, and the larynx. These structures allow us to breathe and speak. They warm and clean the air we inhale: mucous membranes lining upper respiratory structures trap some foreign particles, including smoke and other pollutants, before the air travels down to the lungs.The upper airway not only provides a passage for air to be breathed in and out of the lungs, but it also heats, humidifies and filters the air and is involved in cough, swallowing and speech. The respiratory system is the network of organs and tissues that help you breathe. It includes your airways, lungs, and blood vessels. The muscles that power your lungs are also part of the respiratory system. These parts work together to move oxygen throughout the body and clean out waste gases like carbon dioxide.

when comparing the cases, what similarities are there in the cases that suggest one person committed these murders?