There are some factors that influence cancer. Highly the top answer, smoking can DEFINITELY influence the risk because it ruins the lungs. On the other hand, heredity can influence it, too. If you dwell on it, if most of your family members have cancer, then it was passed down from member to member.
It is the first option. Atmospheric nitrogen is very stable so there fore hard to react with. But bacteria contain molecules that can break the bond of nitrogen.
Answer:
Zebra mussels are spread from one body of water to another by natural flow, carried on the feathers or feet of birds, or by humans in bait buckets or on boats.