At the beginning of the shift, in which order of priority should the practical nurse (PN) assess these four clients? (Arrange from highest priority first to lowest priority last.)

An adult client with an ulcer whose hemoglobin is 9.5 grams/dL.

A young adult with a history of asthma whose arterial pH is 7.48.

An adult woman with vomiting whose potassium is 2.8 mEq/L.

An older adult with dizziness whose O2 saturation is 86%