Answer:
A)provide a basis for virtually all modern anaesthetic techniques
restore tissue oxygen tension by improving oxygen availability in a wide range of conditions such as COPD, cyanosis, shock, severe hemorrhage, carbon monoxide poisoning, major trauma, cardiac/respiratory arrest
aid resuscitation
provide life support for artificially ventilated patients
aid cardiovascular stability
B)Pure oxygen, instead of air, is used to increase the flame temperature to allow localized melting of the workpiece material (e.g. steel) in a room environment. ... Welding metal results when two pieces are heated to a temperature that produces a shared pool of molten metal.