Answer: Density-independent factor Any factor limiting the size of a population whose effect is not dependent on the number of individuals in the population. An example of such a factor is an earthquake, which will kill all members of the population regardless of whether the population is small or large.
Explanation:
Because smoking can cause many different bad things to happen to you some examples would be lung cancer or if you smoke while you are pregnant you cold cause premature or birth defects to the baby, alcohol can just be bad a lot of the time because people can become addicted and loose a lot of money on buying alcohol and/or smoking materials.
I think it my be a structure to life
They release carbon dioxide into the atmosphere which in effect create green house gasses
