<span>D. It shows that the electrons within an atom do not have sharp boundaries.</span>
Mineral because its not a rock
Reaction 3 is the double displacement reaction.
Double displacement reaction occurs when the negatively and the positively charged ions of the compounds interchange their position when the new compound in the product is formed.
<h3>Which is a double displacement reaction?</h3>
In the <u>first reaction</u>, the element lead (Pb) is not an ion and no exchange of the cations or the anions occurs hence it is not a double displacement reaction.
In the <u>second reaction</u>, one compound is getting split into two new compounds and is a decomposition reaction.
In the <u>third reaction</u>,
in
and
in
are anions and cations and exchanges their places to produce two new compounds 
In the <u>fourth reaction</u>, a single compound is generated as the result of the combination reaction and hence, it is not the double displacement reaction.
Therefore,
is the double displacement reaction.
Learn more about double displacement reaction here:
brainly.com/question/10091171
Answer:
See below ~
Explanation:
The calculated values of V/n :
⇒ 1.5/0.3 = 5
⇒ 3/0.6 = 5
⇒ 4.5/0.9 = 5
⇒ 6/1.2 = 5
⇒ 7.5/1.5 = 5
1. From this we understand that the calculated values of V/n remain constant, equal to <u>5</u> in this case.
2. The volume-mole graph will be a straight line passing through the origin. (Attached below)
A.electrons are shared between two different nuclei