The following processes take place sequentially: A system does 523 J of work on its surroundings. The system absorbs 350 J of heat from the surroundings. The system exchanges heat with the surroundings. 582 J of work are done on the surroundings by the system. At the end of step iv, the internal energy of the system is lower by 534 J than its internal energy prior to step i. The amount of heat exchanged by the system in the process of step iii is: -1989 J -1289 J -1105 J -534 J 221 J 350 J 755 J 1289 J None of the above; the correct amount of heat is _____ J