Full outer shell of electrons, they are colorless and odorless ,their melting and boiling points are close together which gives them very narrow liquid range
When a gas is heated to become a plasma, the atoms (or the molecules) of the gas become ionised. In the ionisation, the atoms loose electrons from the exterior energy levels and thus heating to achieve a plasma will create free electrons and ionized atoms (or ionized molecules).
A plasma can not contain neutrons, because neutrons together with protons make the nuclei of the atoms. To free the neutrons from the atomn nuclei there would be necessary HUGE temperatures.
Also a plasma does not contain neutral elements (atoms) or (neutral) molecules, but Ionized atoms and/or molecules and free electrons.
Thus the good answer is d)
In step 1, to increase the potential energy, the iron will move towards the electromagnet.
In step 2, to increase the potential energy, the iron will move towards the electromagnet.
<h3>Potential energy of a system of magnetic dipole</h3>
The potential energy of a system of dipole depends on the orientation of the dipole in the magnetic field.

where;
is the dipole moment- B is the magnetic field


Increase in the distance (r) reduces the potential energy. Thus, we can conclude the following;
- In step 1, to increase the potential energy, the iron will move towards the electromagnet.
- In step 2, when the iron is rotated 180, it will still maintain the original position, to increase the potential energy, the iron will move towards the electromagnet.
Learn more about potential energy in magnetic field here: brainly.com/question/14383738
Pretty much combustion is the reaction of oxygen to a compound that contains carbon and hydrogen. That's why it creates CO2 and H2O