Answer:
A pedometer, or step-counter, is a device, usually portable and electronic or electromechanical, that counts each step a person takes by detecting the motion of the person's hands or hips.
Explanation:
The correct answer would be considered to be answer choice d.
There is not much oxygen available at such a high altitude. For this reason, oxygen tanks would be necessary for both staff and patients, as both would need to remain at a stable oxygen level in order to survive.
