The internal energy of certain system is a function of temperature alone and is given by the formula E = 25 +0.25 t 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, in kj, is
(a) -1.00 (b) -0.50
(c) 0.50 (d) 1.00