Question 4 [ time =3+6+3=12 minutes ] (a) Draw and fully label a diagram depicting the four pressure-volume stages that make up the Carnot cycle for an ideal gas initially placed in thermal contact with a hot source. (b) For each step in the cycle state whether each of (i) heat (q), (ii) work (w), (iii) internal energy (U) (iv) entropy change (S), (v) temperature change (T) and (vi) volume change (V) are >0,0,