1 centisecond (one-hundreth of a second) - the length of time it takes for a stroke of lightning to strike 1 decisecond (one-tenth of a second) - a blink of an eye 1 second - an average person's heart beats once each second 60 seconds - one minute, a long commercial 2 minutes - about as long as a person can hold his or her breath 5 minutes - about as long as anyone can stand waiting at a red light 60 minutes - an hour, about as long as a person can sit in a classroom without glazing over 8 hours - the typical workday in the U.S., as well as the typical amount of sleep a person needs every night 24 hours - one day, the amount of time for the Earth to rotate one time on its axis 7 days - one week 40 days - about the longest a person can survive without food 365.24 days - one year, the amount of time it takes for the planet Earth to complete one orbit around the sun 10 years - one decade 75 years - the typical life span for a human being 5,000 years - the span of recorded history 50,000 years - the length of time homo sapiens has existed as a species 65 million years - the length of time dinosaurs have been extinct 200 million years - the length of time mammals have existed 3.5 to 4 billion years - the length of time that life has existed on earth 4.5 billion years - the age of planet Earth 10 to 15 billion years - the suspected age of the universe since the big bang &lt;&lt; Prev Page Intro Next Page &gt;&gt; Table of Contents: &#155 Introduction to How Time Works &#155 Time's Origins &#155 Clocks &#155 Time Zones &#155 Daylight-Saving Time &#155 The Calendar &#155 B.C. and A.D. &#155 Lots More Information!
(the length of time; takes; for a stroke of lightning; to strike 1 decisecond) (anyone; waiting; L:at a red light) (the longest a person; can survive; ) (the length of time mammals have existed 3.5 to 4 billion years - the length of time; gt; Prev Page Intro Next Page &gt) (a person; can sit; in a classroom) (the Earth; to rotate; T:one time; on its axis; T:one week) (a human; being; 50,000 years - the length of time homo sapiens has existed as a species 65 million years - the length of time) (an average person's heart; beats; once each second 60 seconds - one minute, a long commercial 2 minutes - about as long as a person can hold his or her breath 5 minutes - about as long as anyone can stand waiting at a red light 60 minutes - an hour, about as long as a person can sit in a classroom without glazing over 8 hours - the typical workday in the U.S., as well as the typical amount of sleep a person needs every night) (mammals; have existed; 3.5; T:to 4 billion years) (a person; can hold; ) (the length of time; has existed; L:on earth) (dinosaurs; have been; extinct; T:200 million years) (it; takes; for the planet; to complete one orbit around the sun; 75 years) (anyone; can stand; waiting at a red light) (homo sapiens; has existed; as)
the length of time anyone the longest a person the length of time mammals have existed 3.5 to 4 billion years - the length of time a person the Earth a human an average person's heart mammals a person the length of time dinosaurs it anyone homo sapiens
takes waiting can survive gt can sit to rotate being beats have existed can hold has existed have been takes can stand has existed
for a stroke of lightning to strike 1 decisecond
L:at a red light
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in a classroom
T:one time on its axis T:one week
50,000 years - the length of time homo sapiens has existed as a species 65 million years - the length of time
once each second 60 seconds - one minute, a long commercial 2 minutes - about as long as a person can hold his or her breath 5 minutes - about as long as anyone can stand waiting at a red light 60 minutes - an hour, about as long as a person can sit in a classroom without glazing over 8 hours - the typical workday in the U.S., as well as the typical amount of sleep a person needs every night
3.5 T:to 4 billion years
L:on earth
extinct T:200 million years
for the planet to complete one orbit around the sun 75 years
waiting at a red light
as