
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
In an office, the boss gives the secretary a series of documents to be handled during the day, delivered in the order from 1 up to 12. It's the secretary's practice to stack these documents and work on them from the top of the stack whenever she has time. Sometimes, she reverses the order of the entire stack before working on them. Today, she informs a colleague over a coffee break that document $10$ has already been processed, without offering more details on the rest of the day's work. The colleague wonders in how many ways the remaining documents might be handled post-coffee break. Assume any not-yet delivered document is added to the top of the stack when delivered, and the secretary could potentially reverse the stack one time after the break.

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