The oldest layers of rock will be at the bottom because as years go on things die and create new settlement that forces the older rock to move further down in to the ground
Aortic valve prevents backflow of blood into the left ventricle and creates the second, dubb sound.
The mitral, tricuspid, pulmonary, and aortic valves are the four heart valves that keep blood flowing in the right direction. Flaps (leaflets) on each valve open and close once per heartbeat.
The mitral and tricuspid valves transport blood from the upper chambers of the heart (the atria) to the lower chambers of the heart (the ventricles). The aortic and pulmonary valves transport blood to the lungs and the rest of the body via the ventricles.
Blood flowing through the heart chambers creates heart sounds as the cardiac valves open and close during the cardiac cycle. The vibrations of these structures caused by blood flow produce audible sounds.
To learn more about valves of the heart, here
brainly.com/question/28266922
#SP4
Answer:
Once water vapor is in the atmosphere, low temperatures cause the vapor to either condense into a liquid or undergo deposition to form ice crystals.
