A tree represents an _________ system.

Explanation

To determine the type of system a tree represents, we can analyze the interactions a tree has with its environment. Here's a step-by-step solution:

### Step 1: Define the Types of Systems
There are three main types of thermodynamic systems:
1. **Open System**: Can exchange both energy and matter with its surroundings.
2. **Closed System**: Can exchange energy but not matter with its surroundings.
3. **Isolated System**: Cannot exchange either energy or matter with its surroundings.

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