converting local standard time (a.m./p.m. and 24-hour) to UTC time, and local day-
light savings time (a.m./p.m. and 24-hour) to UTC:
Converting 24-Hour Time to UTC
Local date a.m./p.m. 24-hour clock UTC
April 10 9:59 a.m. EST 0959 1459
April 10 5:00 p.m. EST 1700 2200
April 10 9:30 p.m. EST 2130 0200 April 11
May 10 9:59 a.m. EDT 0959 1359
May 10 5:00 p.m. EDT 1700 2100
May 10 9:30 p.m. EDT 2130 0100 May 11Note: In the United States, for Eastern Standard Time (EST) add five hours to get UTC time, six hours to
Central Standard Time, seven hours to Mountain Standard Time, and eight hours to Pacific Standard
Time. For Daylight Savings Time, add four hours to Eastern Daylight Time to get UTC time, five hours to
Central Daylight Time, six hours to Mountain Daylight Time, and seven hours to Pacific Daylight Time.
What is the Dewey Decimal System?
The Dewey Decimal System of Classification is a numerical method libraries use to
classify nonfiction publications into groups based on subject. It was invented by Amer-
ican librarian Melville Louis Kossuth Dewey (1851–1931) as a system for small
libraries. The subject of a book is classified by a three-digit numeral that represents
ten classes of subjects (000–999). In order, these are Generalities, Philosophy and Psy-
chology, Religion, Social Science, Language, Natural Science and Mathematics, Tech-
nology (Applied Sciences), Arts, Literature, and Geography and History. For example,
The Handy Math Answer Bookwould be found in the Dewey Decimal System under
the 500s for Natural Science and Mathematics.
A Dewey Decimal classification number is followed by the Cutter number, or Cutter.
This method was invented by Charles Ammi Cutter (1837–1903) and is an alpha-numer-
ic way to represent words or names by using one or more letters followed by one or
more Arabic numerals used decimally. Both systems—the Dewey Decimal System and
Cutter—are together called the “call numbers,” a way of locating every book in a library.
What is a ruler?
Usually made of wood, metal, or plastic, a ruler is a measuring stick. Most rulers have a
straight edge used for drawing straight lines and measuring lengths. The simplest and
most well-known ruler has small scales, measured in terms of inches (or centimeters).
In order to read a ruler, the user needs to know the main divisions. For example,
when looking at a foot ruler, the longest increments are represented by inches and are 399