For a large, \(60 \mathrm{~Hz}\), interconnected electrical system assume that following the loss of two \(1400 \mathrm{MW}\) generators (for a total generation loss of \(2800 \mathrm{MW}\) ) the change in frequency is \(-0.12 \mathrm{~Hz}\). If all the on-line generators that are available to participate in frequency regulation have an \(R\) of 0.05 per unit (on their own MVA base), estimate the total MVA rating of these units.