An interconnected \(60-\mathrm{Hz}\) power system consisting of one area has two turbinegenerator units, rated 500 and \(750 \mathrm{MVA}\), with regulation constants of 0.04 and 0.05 per unit, respectively, based on their respective ratings. When each unit carries a 300-MVA steady-state load, let the area load suddenly increase by 250 MVA.

(a) Compute the area frequency response characteristic \(\beta\) on a 1000-MVA base.

(b) Calculate \(\Delta \mathrm{f}\) in per-unit on a \(60-\mathrm{Hz}\) base and in \(\mathrm{Hz}\).