Thermodynamics Part 3

A sample of an ideal gas is taken through the cyclic process ABCA as shown in figure. It absorbs, 40J of heat during the part AB, no heat during BC and rejects 60J of heat during CA. A work of 50J is done on the gas during the part BC. The internal energy of the gas at A is 1560J. The workdone by the gas during the part CA is :