C.
D.
E.
These should be the main reasons. As Pluto was mainly categorized in dwarf planet for not being able to satisfy the last statement which states that it should have a fixed neighbourhood with other planets.
Explanation:
(1) The nucleus is positive and the electron cloud is positive.
(2) The nucleus is positive and the electron cloud is negative.
(3) The nucleus is negative and the electron cloud is positive.
(4) The nucleus is negative and the electron cloud is negative
The reagents for BaCO₃ is
BaO and CO₂
<em><u>Explanation</u></em>
Reagent is a substance that bring about a chemical reaction when added to a system.
Some reagent may be added to see if a reaction has occurred.
BaO and Co₂ are reagent since they react to produce BaCO₃ as below
BaO(s) + CO₂(g) → BaCO3(s)