As of April 2006, roughly 50 million .com web domainnames were registered (e.g.
Chapter 2, Problem 29(choose chapter or problem)
As of April 2006, roughly 50 million .com web domainnames were registered (e.g., yahoo.com).a. How many domain names consisting of just two letters insequence can be formed? How many domain names oflength two are there if digits as well as letters are permittedas characters? [Note: A character length of threeor more is now mandated.]b. How many domain names are there consisting of threeletters in sequence? How many of this length are there ifeither letters or digits are permitted? [Note: All are currentlytaken.]c. Answer the questions posed in (b) for four-charactersequences.d. As of April 2006, 97,786 of the four-character sequencesusing either letters or digits had not yet been claimed. Ifa four-character name is randomly selected, what is theprobability that it is already owned?
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