Which of the Following Are Statements Related to P₅₀

Multiple Choice

Which of the following are statements related to P₅₀?
I.Normally, a PO₂ of 27 mm Hg produces an SO₂ of 50%.
II.The P₅₀ is a measure of hemoglobin's affinity for oxygen.
III.A normal P₅₀ is accurate when the blood temperature is 37° C, pH is 7.40, and PCO₂ is 40 mm Hg.
IV.Normally, a PO₂ of 47 mm Hg produces an SO₂ of 50%.

A) I, II, III, IV
B) II, III
C) I, II, III
D) II, III, IV