Which of the following configurations follows Hund's rule?

Which of the following represents the ground state electronic configuration of an atom?

Which of the following rules describes the order in which electrons fill various orbitals?

Figure $1$ shows the electron density distribution for a $2s$ orbital. Figure $2$ shows the radial wave function plot for a $2s$ orbital. Which of the following points $(A, B, C, D)$ in Figure $2$ most accurately represents the spherical nodal surface as shown in Figure $1$?

Arrange the following orbitals in increasing order of energy based on the given values of principal quantum number $(n)$ and azimuthal quantum number $(l)$:
$(1) n = 4, l = 1$
$(2) n = 4, l = 0$
$(3) n = 3, l = 1$
$(4) n = 3, l = 2$

How is an electron in an atom identified? State the parameters used.