
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
A solid right prism $PQRSTU$ has a height of $20$, as shown in the diagram. Its bases are equilateral triangles with side length $10$. Points $M$, $N$, and $O$ are the midpoints of edges $PQ$, $QR$, and $ST$, respectively. The prism is sliced into two parts with a straight cut through points $M$, $N$, and $O$. Determine the surface area of solid $QNO$, the part that is sliced off.

Present the answer in LaTex format: \boxed{Your answer}
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