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Triassic period

(Encyclopedia)Triassic period trīăsˈĭk [key], first period of the Mesozoic era of geologic time (see Geologic Timescale, tablegeologic timescale, table) from 205 to 250 million years ago. Throughout the Triassi...

Radio Frequencies (table)

(Encyclopedia)Radio Frequencies

Trigonometric Functions (table)

(Encyclopedia)Trigonometric Functions

Holy Roman Emperors (table)

(Encyclopedia)HOLY ROMAN EMPERORS(including dates of reign) Saxon dynasty Salian or Franconian dynasty Hohenstaufen dynasty and rivals Interregnum, 1254–73 Hapsburg, Luxemburg, and other dynasties ...

Anthropocene

(Encyclopedia)Anthropocene Epoch, an unofficial term used by scientists to describe a period of time—up to the present—in which humanity has impacted the planet on a global scale. The phrase was fir...

Periodic Table of the Elements (table)

(Encyclopedia)Periodic Table of the Elements (showing atomic number and atomic symbol; click on atomic symbol for more detailed information) Lanthanide Series(Rare Earth Elements) Actinide Series(Radioactive Rar...

Elements (table)

(Encyclopedia)Elements 1 Parentheses indicate most stable isotope; brackets enclose lower and upper bounds of weight variation. ...

Formulas for Various Areas (table)

(Encyclopedia)Formulas for Various Areas 1 The abbreviations used are: b = base (length of any side of a plane figure); a = altitude (perpendicular distance from the farthest point of the figure to t...

Permian period

(Encyclopedia)Permian period pûrˈmēən [key] [from Perm, Russia], sixth and last period of the Paleozoic era (see Geologic Timescale, tablegeologic timescale, table) from 250 to 290 million years ago. Many ma...

Common Weights and Measures (table)

(Encyclopedia)Common Weights and Measures Length Area Volume and Capacity (Liquid and Dry) Weight (Mass) ...