
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 certain tunnel is designed as a two-way, four-lane passage, with a total lane width of 22 meters. The height limit for vehicles is 4.5 meters, and the total tunnel length is 25 kilometers. The archway of the tunnel is approximately considered to be the shape of a half-ellipse.

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