I would say that <u>a deadly water-borne microorganism in a city's water source</u> would most quickly devastate a human population, merely because a huge number of people uses this water for some kind of a purpose.
If there is no response and not breathing or not breathing normally, position the infant on his or her back and begin CPR. Give 30 gentle chest compressions at the rate of 100-120/minute. Use two or three fingers in the center of the chest just below the nipples.
source :CPR Instructions For Infants and Small Children
depts.washington.edu/learncpr/infantcpr.html
the answer for this question is true
There are three types of muscle contraction: concentric, isometric, and eccentric.
Concentric: In a concentric contraction, the muscle tension rises to meet the resistance then remains stable as the muscle shortens. During eccentric contraction, the muscle lengthens as the resistance becomes greater than the force the muscle is producing.
Isometric: An isometric exercise is a form of exercise involving the static contraction of a muscle without any visible movement in the angle of the joint.
Eccentric: An eccentric (lengthening) muscle contraction occurs when a force applied to the muscle exceeds the momentary force produced by the muscle itself, resulting in the forced lengthening of the muscle-tendon system while contracting