you are in the lab and notice another student applying cosmetics why is the dangerous and not allowed in the lab​

The cosmetics products have the potential to absorb chemical vapour and dust. Thus, applying cosmetics in the lab enables chemical absorption and can be a reason for skin exposure, particularly in the areas where hazardous chemicals are stored. Thus, eating, drinking, and applying cosmetics in the lab is restricted.

because cosmetics products have the potential to absorb chemical vapour and dust

most community's take hundreds of years to become stable

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.