A CDA certificate is a common credential that is required by most states (child development associates)
Modern firearms use the same principles as muzzleloading firearms. The ignition and burning of gunpowder create pressure. This pressure propels projectile(s) down the bore and out of the muzzle. The first modern firearms used black powder. Since about 1890, modern firearms are designed to use smokeless gunpowder. Smokeless gunpowder creates greater pressures and should not be used in firearms designed for black powder. Watch what happens when the trigger is squeezed on this bolt action rifle.
Answer:
The upper respiratory system includes the nasal cavity (nose), the pharynx and larynx.
Explanation:
Air enters the body through the nose or mouth, this moistens and warms the air that enters since cold dry air will irritate the lungs. The air then travels down the voice box and down the windpipe.
