
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 a linear arrangement, points $A$, $B$, $C$, $D$, $E$, and $F$ are aligned in a straight line such that the distances are $AB = 2$, $BC = 4$, $CD = 6$, $DE = 4$, and $EF = 2$. Semi-circles with diameters $AF$, $AB$, $BC$, $CD$, $DE$, and $EF$ form a shape as illustrated. Calculate the area of the shaded region that is structured similarly (largest diameter minus two smaller ones, and plus three other smaller ones).

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