Landfills are harfull to the environment because many substances cannot decompose like styrofoam and all this matter keeps building up but never decomposes
Answer:do you do
The first line of defense involves which structure(s)?
Explanation:
You start by answering the first question on the list which tells you what to do from there. Pretend your animal was a bird, you might have a key like this:
Does this animal have wings?
yes go to question 2
no go to question 6
Then you just continue until the list doesn't say to do anything else. i.e.:
Is the animal feathered?
yes bird
no go to question 4
