A good rule of thumb to remember is that arteries always take oxygen rich blood away from the heart to the rest of the body and veins carry oxygen poor blood back to the heart. The only two circumstances this is not the case is the Umbilical and pulmonary vasculature. Pulmonary Arteries take oxygen poor blood away from the heart to the lungs to be oxygenated and this oxygenated blood returns to the heart via pulmonary veins.
I don't think so because it doesn't matter
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.
Answergo get a heart monetor
Explanation: