Answer:
i be leave the answer is b
Explanation:
Answer: D) Pulmonary and aortic valves.
Explanation
There are two main heartbeats from a healthy heart.
The first beat is called the S1 or the lub, and it occurs when the atrioventricular valves (comprising the mitral and tricuspid valves) close.
The second beat is called the S2 or the dub, and it occurs when the semilunar valves (comprising the aortic and pulmonary valves) close.
Listening for heart beats is an essential part of cardiac auscultation.
Answer:
B
Explanation:
It is believed that the carbon stored in ancient dead plants is what makes up fossil fuels.
D. wolves catch prey by hunting in packs trust me i got it right
Answer:
maybe you should repost this in business? or computer technology