If he sprained his ankle and you know he's n pain, then you should see the doctor or make an appointment. If the injury is severe then take him or her to the emergency room.
Endurance is the answer i think you're looking for.
The blood ph level is not maintained by the respiratory system.
Phase C. 3 of clinical testing is required by the FDA before drug approval and uses the greatest number of subjects. These clinical trials are randomized and controlled trials on large patient groups.
