I just wish there was someone for me out there in this world..

Your answer is  d.)relationship between pressure and air volume and led to the understanding of how respiration works

If it's a smaller child or infant, place one on the middle of the chest and on the child's back. (if it is a bigger child with enough room for two, place one on the upper right/your left of the chest, and one on the lower left/your right) the pads should never touch each other.