Calculate the quantity of the required to generate \(1 \mathrm{~kg}\) of steam at a pressure of 8 bar from water at \(30^{\circ} \mathrm{C}\)

(a) when dryness fraction is 0.9 ,

(b) when steam is just dry, and

(c) when it is superheated at constant pressure to \(300^{\circ} \mathrm{C}\) Assume \(c_{p s}=2.5 \mathrm{~kJ} / \mathrm{kg}\). K.