A. easily combines chemically with other substances is your answer.
Spores in the air or contamination through some sort of insect interaction. In an open system, there are billions of microbial agents floating around. With an open container containing a food source and time, the likelihood of contamination is nearly %100.
Answer:
liquid, solid, and gas
Explanation: It depends where the molecules are moving. When a solid the molecules are vibrating and are all together, compact, the molecules are also very slow. When a liquid the molecules are moving back and forth, up and down, and are less compact, but moving faster. When a gas, the molecules move everywhere very quickly, moving super fast.