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In this article we present a theoretical investigation of the inelastic light scattering by electronic excitations in a quantum dot charged with 42 electrons. The energies and wave-functions of the multielectronic states involved in the Raman process, are obtained in the framework of Random Phase Approximations (RPA). Charge-Density (CDE) and Spin-Density (SDE) excitations are identified by evaluating the multipolar energy-weighted sum rules (EWSR). We compute Raman spectra for different values of the incident laser energy in both, polarized and depolarized geometry. Calculated Raman spectra with anexcitation energy below the bandgap reveals several advantages for identifying and following individual peaks. The breakdown of Raman polarization selection rules under the influence of an external magnetic field is studied by calculating the polarization ratios. The breakdown of these selection rules under resonant excitation with the semiconductor bandgap, which we termed Raman intensity jump-rule, is found and proposed as a useful tool for identifying the character (charge or spin) of electronic excitations. We found that Raman spectra in the extreme resonance region are dominated by strong peaks associated to single-particle excitations (SPEs). The interference effects between the intermediate states in the Raman transition amplitude are evaluated. The main features of Raman spectra with excitation energy well-above the bandgap are qualitatively reproduced in terms of lifetimes of the intermediate states. [ABSTRACT FROM AUTHOR]