Heat Engine Cycle: Answers to (i), (ii) & (iii)

[hann8559]

Does anyone can help me in this question?

Two reversible heat engines operate in series between a source at 600C and a sink at 30C.
If the engines have equal efficiencies and the first rejects 400 kJ to the second, calculate:
(i) the temperature at which heat is supplied to the second engine;
(ii) the heat taken from the source;
(iii) the work done by each engine.
Assume that each engine operates on the Carnot cycle.
Answers: 241.3C; 679.1 kJ; 279.1 kJ and 164.4 kJ.

Homework Equations

The Attempt at a Solution

 

[rock.freak667]

You will need to post some attempt at the solution before anyone can help you.

First of all draw the engine diagram showing the heat and work flows. What is the equation to get the carnot efficiency of an engine?