I think the answer is yes and No. . Yes, Fish are considered a sustainable resource. A sustainable resource is a resource an environmental resource that doesn't harm the environment. Fish are helping the environment. However fish have waste and the waste is dangerous to the environment.
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.
A covalent bond is a bond between 2 non-metals (sharing of electrons between atoms), where ionic is between a metal and a non-metal (the transfer of electrons). Standard covalent bonds are usually weaker then ionic bonds.
Covalent - Hydrogen + Chlorine = Hydrogen Chloride (HCl)
Ionic - Sodium + Chlorine = Sodium Chloride (NaCl)
Answer:
A is the kingdom bcz other are phylum class, etc
