Question

a thermodynamic system in which matter and energy may enter or exit.
a thermodynamic system in which energy may enter or exit, but matter may not enter or exit.
a thermodynamic system in which neither energy not matter may enter or exit.
closed system
isolated system
open system

Explanation:

1. An open - system allows both matter and energy to enter or exit.
2. A closed - system allows energy to enter or exit but not matter.
3. An isolated - system allows neither energy nor matter to enter or exit.

Answer:

A thermodynamic system in which matter and energy may enter or exit: Open System
A thermodynamic system in which energy may enter or exit, but matter may not enter or exit: Closed System
A thermodynamic system in which neither energy nor matter may enter or exit: Isolated System