If both the engines have the same heat input and output, then the

Question

One reversible heat engine operates between 1000 K and T₂ K and another reversible heat engine operates between T₂ K and 400 K.  If both the engines have the same heat input and output, then the temperature T₂ must be equal to                

       (a)    582.7 K          (b)  632.5 K

       (c)    682.8 K          (d) 732.5 K