Natural barriers include the skin, mucous membranes, tears, earwax, mucus, and stomach acid.
Being sedentary means you don't move around (stay in one place).
People who are sedentary could play video games at their computer all of the time, which means they stay up late.
Staying up late leads to sleep deprivation.
Thus, video gamers could have sleep deprivation.
Explanation
Sleep can alter your sports performance because of how it affects the body during exercise. Therefore sleep can help your body in many things such as learning and exrisices.
Answer:
See explanation below.
Explanation:
From the definition of adjacent angles, the sum of measure of all the adjacent angles on a horizontal line equals to
.
From the given figure, we have:

And from the definition of alternate angles, we have:
