
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
Calculate the arithmetic mean of the set $\{8, 88, 888, 8888, \ldots, 888888888\}$, a sequence where each following integer is formed by adding another digit '8' to the previous one. Find out which digit from '0' to '9' is not present in the calculated mean $N$, which is an integer with all distinct digits.
A) 0
B) 2
C) 4
D) 6
E) 8

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