Answer:
Innate immunity you are born with.
Acquired immunity you need to work on over time
Explanation:
Poison ivy for example. Come people are born immune to it, while others have to be around it a lot, (agonizingly so), and they will build up immunity to it's poison.
DNA is made up of the individual units called Nucleotides.
Answer:The placement of fossils throughout the sruface layers of earth
Explanation:
Each layer of earth has a different density the more in you go with the layers the more density is going to show up.
Crust-2.2g/cm^3
Upper mantle-3.4g/cm^3
Lower mantle-4.4g/cm^3
Outer core-9.9g/cm^3
Inner core-12.8g/cm^3
Hope I helped in something, Sorry if I didn't gave it my best shot:)