
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 the sequence $\{a_n\}$, if there exists $a_k$ such that " $a_k > a_{k-1}$ and $a_k > a_{k+1}$ " holds (where $k\geq2$, $k\in \mathbb{N}^*$), then $a_k$ is called a peak of $\{a_n\}$.

(Ⅰ) If $a_n = -|n-7|$, then the peak of $\{a_n\}$ is ______.

(Ⅱ) If $$a_{n}= 
  \begin{cases}
    n^2 - tn & \text{for } n \leq 2 \\
    -tn + 4 & \text{for } n > 2
  \end{cases}$$
and $\{a_n\}$ has a peak, then the range of real number $t$ is ______.

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