(a) How many strings of length 8 have distinct characters and do not start with "a"?(b) How many strings of length 8 have distinct characters that appear in alphabetical order (e.g.,"acdefxyz" but not "cadefxyz")?(c) How many strings of length 8 have exactly 2 a's and exactly 2 b's?(d) Assume you are writing words in a page, each word is a string of length 8. How many differentwords must be written in that page in order to guarantee that at least 3 of them start with thesame letter? ) (2x) (y + 2)xConsider the alphabet of the 26 lower-case English letters {a, b, z}...

B. The number of string that appears in alphabetical order :

(b) How many strings of length 8 have distinct characters that appear in alphabetical order (e.g., "acdefxyz" but not "cadefxyz")? (c) How many strings of length 8 have exactly 2 a's and exactly 2 b's?

(b) How many strings of length 8 have distinct characters that appear in alphabetical order (e.g., "acdefxyz" but not "cadefxyz")? (c) How many strings of length 8 have exactly 2 a's and exactly 2 b's?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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