Here's a short story:

The Dewey Decimal Classification (DDC), or Dewey Decimal System, is a proprietary library classification system first published in the United States by Melvil Dewey in 1876. It has been revised and expanded through 23 major editions, the latest issued in 2011, and has grown from a four-page pamphlet in 1876. It is also available in an abridged version suitable for smaller libraries. It is currently maintained by the Online Computer Library Center (OCLC), a non-profit cooperative that serves libraries. OCLC licenses access to an online version for catalogers called "WebDewey". 

The Decimal Classification introduced the concepts of "relative location" and "relative index" which allow new books to be added to a library in their appropriate location based on subject. Libraries previously had given books permanent shelf locations that were related to the order of acquisition rather than topic. The classification's notation makes use of three-digit Arabic numerals for main classes, with fractional decimals allowing expansion for further detail. Using Arabic numerals for symbols, it is flexible to the degree that numbers can be expanded in linear fashion to cover special aspects of general subjects. A library assigns a classification number that unambiguously locates a particular volume in a position relative to other books in the library, on the basis of its subject. The number makes it possible to find any book and to return it to its proper place on the library shelves. The classification system is used in 200,000 libraries in at least 135 countries. (End of story)

Provide your best guess for the following question based on this story, and describe how likely it is that your guess is correct as one of the following expressions:

Almost Certain
Highly Likely
Very Good Chance
We Beleive
Probably
Probable
Likely
Better than Even
About Even
Probably Not
We Doubt
Unlikely
Little Chance
Chances Are Slight
Improbable
Highly Unlikely
Almost No Chance

Give ONLY the guess and your confidence, no other words or explanation. For example:

Guess: <most likely guess, as short as possible; not a complete sentence, just the guess!>
Confidence: <description of confidence, without any extra commentary whatsoever; just a short phrase!>

Here are a few examples of questions and answers:

Question: Who published the DDC?
Guess: Melvil Dewey
Confidence: <appropriate level of confidence in this guess>

Question: When?
Guess: 1876
Confidence: <appropriate level of confidence in this guess>

Question: Where?
Guess: the United States
Confidence: <appropriate level of confidence in this guess>

Question: Is DDC an acronym?
Guess: yes
Confidence: <appropriate level of confidence in this guess>

Question: What does it stand for?
Guess: Dewey Decimal Classification
Confidence: <appropriate level of confidence in this guess>

Question: Is it called anything else?
Guess: Dewey Decimal System
Confidence: <appropriate level of confidence in this guess>

Question: What concepts were introduced with this program?
Guess: "relative location" and "relative index"
Confidence: <appropriate level of confidence in this guess>

Question: What criteria did it use to put the books in a location?
Guess: subject
Confidence: <appropriate level of confidence in this guess>

Question: What type of numerals did it use for main classes of books?
Guess: Arabic
Confidence: <appropriate level of confidence in this guess>

Question: 2 digit?
Guess: no
Confidence: <appropriate level of confidence in this guess>

Question: How many?
Guess: Three
Confidence: <appropriate level of confidence in this guess>

Question: Were fractional decimals used as well?
Guess: yes
Confidence: <appropriate level of confidence in this guess>

Question: What did this allow expansion for?
Guess: further detail.
Confidence: <appropriate level of confidence in this guess>

Question: Was the use of numerals rigid?
Guess: no
Confidence: <appropriate level of confidence in this guess>

Question: How was its use described?
Guess: it is flexible
Confidence: <appropriate level of confidence in this guess>

Question: How many editions have there been?
Guess: 23
Confidence: <appropriate level of confidence in this guess>

Question: When was the last released?
Guess: 2011,
Confidence: <appropriate level of confidence in this guess>

Now answer the following question in the same format.

Question: How many pages did it originally have?

four