For either nitrous oxide analgesia or intravenous sedation using diazepam (Valium) in a healthy adult patient, you would require
1. that the patient be supine.
2. that the patient have no food or drink for four hours previously.
3. that the patient possess an electrocardiogram.
4. that emergency drugs are available.
5. that oxygen is available.

(1) (2) (4) (5)

(1) (2) (5)

(1) (2) (3)

(2) (3) (4) (5)

All of the above.