Carnot cycle,please help me solve this!!

Click here to see the diagram
http://i594.photobucket.com/albums/tt26/PRINCESS_HALIZA_2009/IMG_2181.jpg

The diagram shows a reversible cycle of a 1 mol ideal gas.Given the temperature at A is T0 and gas constant is R.Specific heat γ= 5/3.

1.Find the all the heat absorbed in 1 cycle.
2.Find the all the heat released in cycle.
3.Find the efficiency of the heat engine.
4.Find the efficiency of the Carnot Cycle.
5.Find the change in entropy from point A to point C

I know this is a multiple question but I really need help.Please show me the solution and explanations,please.

N---O---T---I---C---E:


======================================…

CONSIDER PROCESS A TO B ( Constant Volume):

General Formula: Q (A==>B) = n x Cv x (Tb - Ta)

where:

n = # of moles of gas = 1 mole
Cv = specific heat at constant volume = unknown
Tb = unknown
Ta = To

Solve for Cv:

γ = 5 / 3 = Cp / Cv ( Thermodynamic relationship of specific heats )
Cv = (3/5)Cp ====> equation 1

But Cp = Cv + R, where R = 8.314 J/mol.K (also a Thermodynamic concept)
Cp = Cv + 8.314 J/mol.K =====> equation 2

Combine equation 1 and 2:
Cv = (3/5)[Cv + 8.314 J/mol.K] ====%2