Answer:
D) four.
Explanation:
The two atria hold the blood that circulates away from the heart. The heart has four one-way valves, which open and close with each heartbeat. The tricuspid valve and the mitral valve are located between the atria and allow the blood to flow from the atria to the ventricles. Also you don't have to but mind marking Brainliest?
<span>The system proved suitable for patients with unilateral cleft lip and palate for whom the generated nasal mask continuous positive airway pressure remained constant between 5 to 7 cm of water but failed in the patient with bilateral cleft lip and palate. None of the patients had to be ventilated due to respiratory failure, and all survived to discharge.
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Cut the snacks and pastries