13-13= 0, 19-13= 6, so then 0-6= -6
Answer:
The correct answer is B respiratory system
Explanation:
Respiratory system of our body play a significant role in the inhalation of oxygen into and exhalation of the waste product known as carbon dioxide from our body.
Respiratory system basically composed of diaphragm and respiratory muscles.The volume of diaphragm increases during inhalation and decreases during exhalation. This is called the elastic nature of lungs which helps in efficient gas exchange.
Explanation:
Ecosystems contain biotic or living, parts, as well as abiotic factors, or nonliving parts. Biotic factors include plants, animals, and other organisms. Abiotic factors include rocks, temperature, and humidity. Every factor in an ecosystem depends on every other factor, either directly or indirectly
<u>Hope this helps you.</u>
<u>Hope this helps you.Let me know if you have any other questions :-):-)</u>