Answer: Atmosphere
Explanation:
Atmosphere is the part of the earth, known as the gaseous part, since it contains gases such as nitrogen (about 78%), oxygen (about 21%), Carbondioxide (about 0.03%), and rare gases to make the rest.
Thus, atmosphere contains the most whole of oxygen and carbon dioxide
Smoking ruins your lungs making it harder to breath and get oxygen
you need oxygen when you exercise so you don't faint
smokers get less so it is harder for them, its like trying to exercise while breathing through a sponge or a straw os
The fossil shows evidence of how animals lived on Earth in the past and shows history about animals that may be extinct now or have evolved since then, which would show development in the animal in the fossil.
Answer:
A mutation is a change that occurs in our DNA sequence, either due to mistakes when the DNA is copied or as the result of environmental factors such as UV light and cigarette smoke. Mutations can occur during DNA replication if errors are made and not corrected in time.
