Answer:

Explanation:
Complete ionic equation : In complete ionic equation, all the substance that are strong electrolyte and present in an aqueous are represented in the form of ions.
Net ionic equation : In the net ionic equations, we are not include the spectator ions in the equations.
Only the species which are present in aqueous state dissociate.
Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.
(a)
The balanced molecular equation will be,
The complete ionic equation in separated aqueous solution will be,
In this equation the species present are,
are the spectator ions.
Hence, the net ionic equation contains specie is

Answer:
I think B but I'm not sure.
Precision relates to how close the answers are to each other, so I’d think it would be D because of the limited range between data points.
Answer: compound
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Copper
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: water
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present. Example: Air