<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>
Option B: 2, 8, 18, 32.
2 in the K shell, 8 in L shell, 18 in M shell and 32 in N shell.
Answer:
a. single replacement reaction
Explanation:
Mg(s) + 2HCl(aq)——-> H2(g) + MgCl2(aq)
Mg replaces H, so this is a single replacement reaction.
Answer: Atomic number
Explanation: Atomic numbers never change, they stay the same which is why they are what elements are identified by
