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Correct Answer: B) 90%.
Correct Answer: D) Capillaries.
Correct Answer: D) Organ/muscle.
Correct Answer: B) 60-100 beats per minute.
Correct Answer: A) 3.
Correct Answer: D) Blood vessels.
Correct Answer: A) Arteries.
Correct Answer: A) About 10 seconds.
Correct Answer: A) White Blood Cells.
Correct Answer: C) Mitral valve.
Correct Answer: C) Hypertension.
Correct Answer: C) Septum.
Correct Answer: A) Ventricles.
Correct Answer: A) Pulmonary vein.
Correct Answer: C) Right atrium.
Correct Answer: C) Kidney.
Correct Answer: B) Thicker.
Correct Answer: A) Atria.
Correct Answer: D) Fight pathogens.
Correct Answer: B) Blood vessels.
Correct Answer: C) Exchange for oxygen.
Correct Answer: B) Antigens.
Correct Answer: C) Mammals only.
Correct Answer: B) Tricuspid valve.
Correct Answer: C) 2 billion times.