Question

1. why might multiple doses of antibiotics or antiseptics not kill 100% of bacteria in a population?

Explanation:

Bacteria populations may have resistant strains. Some bacteria may be in a dormant state and not affected by antibiotics. Also, antibiotics may not reach all bacteria in the body due to anatomical barriers or poor distribution.

Answer:

Bacteria may have resistance, be dormant, or be in areas unreachable by antibiotics.