After your buddy checks to see that your air is turned all the way on: A. You are ready to enter.
B. Reach back and double check it yourself.
C. Take several deep breaths from your regulator while watching your SPG for changes in pressure.
D. None of the above.

As you sit in the library with your friend studying for your weekly quiz on the integumentary system, you come upon an article about the hazards of prolonged exposure to the sun's rays. your curious nature leads you to research the subject further. you're fascinated to learn that minimal exposure to the sun allows you skin to manufacture vitamin d, which is important to maintain homeostasis. you also read that although sunscreen can protect you from the ultraviolet (uv) rays of the sun, some medications can actually increase a person's sensitivity to the sunlight.