<span>The answer is: at least at least 2 hours after a meal is when chest physiotherapy should be performed. This is the answer because performing chest physiotherapy closer than that to a meal will increase the risk of vomiting and aspiration. Also, performing it immediately before a meal could tire our the client and impair the ability to eat.</span>
Answer Internal and external environmental factors, like gender and temperature, influence gene expression. ... Similarly, drugs, chemicals, temperature, and light are among the external environmental factors that can determine which genes are turned on and off, thereby influencing the way an organism develops and functions.
Explanation:
The correct answer is B. Oxygen.
Oxygen, as a part of the atmosphere, also participates in UV protection, besides being necessary for breathing.