A single covalent bond exists when two atoms share ………………pair(s) of
valence electrons

the answer is lactic acid from anaerobic respiration. the acid in lactic acid is what creates sore and burning muscles. if you think about how acid burns that will give you a clue for questions like this.

answer;

-phase iii

explanation;

phase three begins with the transition of a recovered individual to a phase three team of the appropriate service. this phase usually takes place at a military medical facility in the united states. one of the goals of phase three is family reunification.