<prompt>  A man is found comatose in his room, having taken an unknown number of sleeping pills. An aerial blood sample yields the following values: pH 7.10, HCO3 - 12 meqliter, PaCO2 66 mm Hg. This patients acid - base status is most accurately described as:Uncompensated metabolic acidosisUncompensated respiratory acidosisMixed respiratory and metabolic acidosisRespiratory acidosis with paial renal compensation 