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NARA [144]
3 years ago
13

30 POINTS!!!!!!

Biology
2 answers:
vladimir1956 [14]3 years ago
8 0
I believe the answer is B.
satela [25.4K]3 years ago
3 0
B. The valves of the aorta and pulmonary artery close, producing the first heartbeat. Is the correct answer. Hope this helped. Have a good day! :)
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