Buffers in Medicine (b)?

[cRyStaL c]

b) Carbon dioxide (CO_2) and bicarbonate (HCO_3^-) concentrations in the bloodstream are physiologically controlled to keep blood pH constant at a normal value of 7.4.

Physicians use the following modified form of the Henderson-Hasselbalch equation to track changes in blood pH: pH = pKa + log { [HCO_3^-] / (0.03)(P_(CO_2)) }

where [HCO_3^-] is given in millimoles/liter and the arterial blood partial pressure of CO_2 is given in mmHg. The pKa of carbonic acid is 6.1. Hyperventilation causes a physiological state in which the concentration of CO_2 in the bloodstream drops. The drop in the partial pressure of CO_2 constricts arteries and reduces blood flow to the brain, causing dizziness or even fainting.

If the normal physiological concentration of HCO_3^- is 24 mM, what is the pH of blood if P_(CO_2) drops to 27.0?