What prefixesdefine the powers of ten?
Many standard prefixes are used to represent powers of ten, most of which are
employed quite frequently to express various units. We are all familiar with some of
them, including kilo- (from the Greek chilioi,or “a thousand”), milli- (from the Latin
mille,or “thousand”) , and micro- (from the Greek mikros,or “small”). The following
chart defines some prefixes representing the powers of ten:Prefixes for Powers of Ten
Multiple Name
1018 exa
1015 peta
1012 tera
109 giga
106 mega
103 kilo
102 hecto
10 deka
10 ^1 deci
10 ^2 centi
10 ^3 milli
10 ^6 micro
10 ^9 nano
10 ^12 pico
10 ^15 femto
10 ^18 attoTHE CONCEPT OF ZERO
What is a placeholder?
A placeholderis a number that, as the name implies, holds a place. Initially, various
cultures used a placeholder—often a dot or a space—to show an empty spot or place
not used in a numeral (or other way of counting). This was in place of what we now
call a zero (0), a symbol that is not only a placeholder but also an essential number in
our numeration system. (For more about the evolution of the symbol zero [0], see
“History of Mathematics.”)What are the definitions of zeroand non-zero?
Those who use the Hindu-Arabic numeration system are all familiar with the concept
of “zero” (0), and its importance. The symbol “zero” represents a valuable placeholder;
90 it is also the additive identity element of an algebraic system (when a number and its