The internal energy of a certain system is a function of temperature alone and is given by the formula : E = 25 + 0.25t kJ. If this system executes a process for which the work done by it per degree temperature increase is 0.75 kN.m, the heat interaction per degree temperature increase is :

(a) – 1.00 kJ

(b) – 0.50 kJ

(c) + 0.05 kJ

(d) 1.00 kJ