The answer is B. chemicals.
the reason its b is because A= bacteria but u have to clean the bacteria in the water so its not A and its not c. becouse that will be just turning the ice into water .so the answer is b. becouse we use chemicals everyday to get rid of bacteria and waste
<span>Hope this helps.
The skeletal system makes up the framework of the body and allows us to move when our muscles contract.</span>
Answer: Gasses are exchanged across the alveolar membrane.
The exchange of gasses takes place across the alveolar membrane of the lungs. Our respiratory system are composed of nose, pharynx, larynx, trachea, bronchi, and lungs (alveoli) where gas exchanges between the blood and external environment by diffusion. Moreover, during the gas exchange, the oxygen enters the blood while carbon dioxide enters the alveoli.
<h2>Answer:</h2>
<u>Natural gas is indoor pollutant</u>
<h2>Explanation:</h2>
From the options given above smog and vehicle exhaust are outdoor pollutants. Oxygen is not a pollutant at all. The only option left is natural gas. When we cook food or use heaters we use natural gas so the burning of natural gas pollutes the indoor environment that is why we can say that natural gas is indoor pollutants.
When two people avoid eye contact
