i can help you with this question!
Most likely it's A because you could change the height of the plant and that's what a independent variable is, a factor you can change in order to find out will happen, Hope this helps
Answer:
dont let him deltete ur question okay kiddo??
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.