To know where it rightfully belongs to. Variation of certain traits is caused by multiple factors of an individual of the same kind. Depending on their physical appearance, their environment and nature of survival.
Hope this might help.
West Nile lead to a decline in susceptible avian and human hosts, with a subsequent decline in the number of cases since 1997
It is definitely not a primary source: this would be a book itself.
Now, is it a tertiary source? I don't think so: the author of the review should have read the book and should only be referring to this book in the review.
I think it's a secondary source.
Answer:
No
Explanation:
Only what state it is in, soild, liquid or gas. Particals never change duering this.
The Economy<span> and Environment. </span>Estuaries<span> are </span>important<span> natural places. They
providegoodsandservicesthat are </span>economically<span> and </span>ecologically<span> indispensable.
sry if wrong</span>