A proton is a very tiny particle inside an atom. The mass of the proton is estimated to be 0.00000000000000000000000167 g. What is the mass of a proton in specific notion? A. 1.67 x 10 24 g
B. 16.7 x 10 -25 g
C. 167 x 10 -26 g
D. 1.67 x 10 -24 g

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.