D) ba is the correct answer
<u>Answer:</u> The ion formed by lithium element is 
<u>Explanation:</u>
Ions are formed when an atom looses or gains electrons.
If an atom gains electrons, it leads to the formation of negative ions known as anions. For Example: Fluorine gains 1 electron to form
ions.
If an atom looses electrons, it leads to the formation of positive ions known as cations. For Example: Sodium looses 1 electron to form
ions.
Lithium is the 3rd element of the periodic table having 3 electrons.
The electronic configuration of lithium element = 
This element will loose 1 electron to attain stable electronic configuration and will lead to the formation of
ion.
Hence, the ion formed by lithium element is 
Answer:
First shell is lower
Explanation:
The electron has to absorb energy to excite and go to higher energy levels/ shells and should release energy to go to lower energy levels/ shells. This means higher the shell , more energy is required and vice versa
When it stays on top it has potential energy converted to mechanical energy because the turbines and rods are put to work.