The nurse is caring for a diabetic patient in renal failure. Which laboratory findings are consistent with metabolic acidosis?

pH 7.35, PaCO2 40 mm Hg, HCO3- 25 mEq/L

pH 7.4, PaCO2 35 mm Hg, HCO3- 35 mEq/L

pH 7.3, PaCO2 36 mm Hg, HCO3- 19 mEq/L

pH 7.45, PaCO2 45 mm Hg, HCO3- 30 mEq/L