
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
Starting from the Winter Solstice, the lengths of the shadows of the twelve solar terms, in order, from Minor Cold, Major Cold, the Beginning of Spring, Rain Water, Awakening of Insects, the Vernal Equinox, Pure Brightness, Grain Rain, the Beginning of Summer, Minor Fullness, and Grain in Ear form an arithmetic progression. The sum of the lengths of the shadows on the Winter Solstice, the Beginning of Spring, and the Vernal Equinox is 31.5 feet, and the sum of the lengths of the shadows on the first nine solar terms is 85.5 feet. Determine the length of the shadow on Minor Fullness.

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