In a closed system, no mass may be transferred in or out of the system boundaries. The system always contains the same amount of matter, but heat and work can be exchanged across the boundary of the system. Whether a system can exchange heat, work, or both is dependent on the property of its boundary.

See options at the end. Can we conclude that can work be done in a closed system?

Select from:
[a]. no;
[b]. yes;
[b].