<span>The correct answer among
the choices given is the last option. Galaxies are classified according to
their shapes or visual morphology. There three main types of galaxies
currently. They are the elliptical, spiral and irregular. Elliptical galaxies
are like a spheroid or an elongated sphere. Spiral galaxies are characterized
and distinguished by having a bulge, a disk and a halo. Lastly, irregular
galaxies do not have regular or symmetrical shape.</span>
Calculations in chemistry can range from large numbers to the smallest number in decimals to be more accurate in data results. When this occurs using scientific notations allows you to note down results regardless of size as accurate as possible without writing a lot of numbers.
The electrons are what determines the energy level and reaction of the valence shell, hope it helps ❤️✌️
In metals, some of the electrons (often one per atom) are not stuck to individual atoms but flow freely among the atoms. Of course, that's why metals are such good conductors of electricity. Now if one end of a bar is hot, and the other is cold, the electrons on the hot end have a little more thermal energy- random jiggling- than the ones on the cold end. So as the electrons wander around, they carry energy from the hot end to the cold end, which is another way of saying they conduct heat.
Here, sodium is a metal which possesses an extra (valence) electron carries the heat around its body as it is a free electron, which enables sodium to conduct thermal energy.
Hope this help :)
