Answer
See the explanation
Work Step by Step
The search tree generated by breadth-first search for the eight-puzzle problem starting from the given initial state:
```
1
/ \
2 3
/ \ / \
4 5 6 7
| | | |
8 9
```
Each node represents a possible state of the puzzle, with the numbers indicating the position of the tiles. This tree represents the exploration of possible moves from the initial state in a breadth-first manner.
