Eons and eras - Paleozoic – The Paleozoic Era is the earliest of three geologic eras of the Phanerozoic Eon. It is the longest of the Phanerozoic eras, lasting from 541 to 251.902 million years ago, and is subdivided into six geologic periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian.

 
The end of the Paleozoic Era came with the largest mass extinction in the history of life on Earth, wiping out 95% of marine life and nearly 70% of life on land. ... Geologic Time Scale: Eons, Eras, and Periods. The Carboniferous Period. The Permian-Triassic Extinction Event. The Ordovician Period (488-443 Million Years Ago) A Fossil …. Ncaa exhibition games

The Proterozoic record The geologic record of the Proterozoic Eon is more complete than that for the preceding Archean Eon. In contrast to the deep-water deposits of the Archean, the Proterozoic features many strata that were laid down in extensive shallow epicontinental seas; furthermore, many of those rocks are less metamorphosed than …What is eon era period and age epoch? Epochs are the smallest divisions. Many epochs make up a period, many periods make up an era, and many eras make up an eon. In defining the boundaries between major divisions, we often use markers, like the dinosaur extinction or the appearance of certain organisms.The Phanerozoic eon is divided into three eras: the Palaeozoic, an era of arthropods, amphibians, fishes, and the first life on land; the Mesozoic, which spanned the rise, reign of reptiles, climactic extinction of the non-avian dinosaurs, the evolution of mammals and birds; and. the Cenozoic, which saw the rise of mammals.e·on. also ae·on (ē′ŏn′, ē′ən) n. 1. An indefinitely long period of time; an age. 2. The longest division of geologic time, containing two or more eras. [Late Latin aeōn, from Greek aiōn; …Therefore, moving upward on the scale, each division is younger. The time scale is divided into units called eons, eras, periods and epochs. Eon. The largest formal unit of geologic time; it is measured in billions of years. There are three eons: the Archean, Proterozoic, and Phanerozoic. Era.The oldest — and by far the longest — is called the Precambrian. It is divided into Eons known as the Hadean (HAY-dee-un), Archean (Ar-KEY-un) and Proterozoic (Pro-tur-oh-ZOE-ik). After the Precambrian come the Paleozoic Era and Mesozoic Era. Last butProterozoic Eon, the younger of the two divisions of Precambrian time, the older being the Archean Eon. The Proterozoic Eon extended from 2.5 billion to 541 million years ago and is often divided into the Paleoproterozoic (2.5 billion to 1.6 billion years ago), the Mesoproterozoic (1.6 billion to 1 billion years ago), and the Neoproterozoic (1 billion to …Eons are the broadest category of geologic time, and we live in the Phanerozoic eon. The three eras of the Phanerozoic eon divides on the basis of characteristic assemblages of life-forms. Log in for more information. Added 8/28/2019 3:31:22 AM This answer ...Devoured on the right by Reform and Nigel Farage, it may take eons to regroup into anything recognisably electable. Labour dare not say it, but 2024 may mark much more than a pendulum swing by ...Name the 4 main geological eons. 1.Hadean eon. 2.Archaean eon. 3. Proterozoic eon. 4.Phanerozoic eon. . What are the 3 eras that the phanerozoic eon covers? 1.Palaezoic era.Eras are subdivided into Periods, which in turn are subdivided into Epochs. Go to the British Geological Survey interactive Geological Timeline http://www.bgs.May 31, 2023 · US Seniors/Graduates (MD or DO) Medical School of Graduation. Contact Medical School of Graduation. Contact Medical School of Graduation. Contact Medical School of Graduation. International Medical Graduates (IMGs) Educational Commission for Foreign Medical Graduates (ECFMG) 215-966-3520. [email protected]. Jurassic Period, second of three periods of the Mesozoic Era. Extending from 201.3 million to 145 million years ago, the Jurassic was a time of global change in the continents, oceanographic patterns, and biological systems. On land, dinosaurs and flying pterosaurs dominated, and birds made their first appearance.The Archean Eon, stretching from 4 to 2.5 billion years ago, is followed by an even longer one, the Proterozoic Era which stretches from 2.5 to 0.54 billion years ago. These eons are long because historically they left very little record of themselves in the rock record, and there really were not any obvious extinction events, one characteristic that defines the …Study with Quizlet and memorize flashcards containing terms like The oldest fossils usually _____. See Concept 25.2 (Page 528) are found above younger fossils contain more radioactive isotopes than younger fossils are found in sediments formed during the Cenozoic era have the longest half-lives are found in the deepest strata, A paleontologist finds a …Precambrian, period of time extending from about 4.6 billion years ago (the point at which Earth began to form) to the beginning of the Cambrian Period, 541 million years ago. The Precambrian encompasses the Archean and Proterozoic eons, which are formal geologic intervals that lasted from 4 billion to about 541 million years ago, and the ...Cenozoic Era. The Cenozoic Era (66 million years ago through today) is the "Age of Mammals." Birds and mammals rose in prominence after the extinction of giant reptiles. Common Cenozoic fossils include cat-like carnivores and early horses, as well as ice age fossils like wooly mammoths. Caves can preserve the remains of ice-age animals …Eons are the broadest category of geologic time, and we live in the Phanerozoic eon. The three eras of the Phanerozoic eon divides on the basis of characteristic assemblages of life-forms. Log in for more information. Added 8/28/2019 3:31:22 AM This answer ...Andrew Alden. Updated on March 18, 2020. This table shows the highest-level units of the geologic time scale: eons and eras. Where available, the names link to more detailed descriptions or significant events that occurred during that specific eon or era. More details beneath the table.Eon, Long span of geologic time. In formal usage, eons are the longest portions of geologic time (eras are the second-longest). Three eons are recognized: the Phanerozoic Eon (dating from the present back to the beginning of the Cambrian Period), the Proterozoic Eon, and the Archean Eon. US Seniors/Graduates (MD or DO) Medical School of Graduation. Contact Medical School of Graduation. Contact Medical School of Graduation. Contact Medical School of Graduation. International Medical Graduates (IMGs) Educational Commission for Foreign Medical Graduates (ECFMG) 215-966-3520. [email protected] divisions of the geologic time scale are organized stratigraphically, with the oldest at the bottom and youngest at the top. GRI map abbreviations for each geologic time division are in parentheses. Boundary ages are in millions of years ago (mya). Major North American life history and tectonic events are included.22 Apr 2020 ... Packing up my shelves this week as we transition from our units on geological eras and prehistoric life towards ancient civilization.The oldest dated zircons dated from about 4.0 Ga — very early in Earth’s history. The Hadean Eon is often characterized by extreme volcanism as Earth continued to cool. Large amounts of water would have been in the material which formed the Earth. Water molecules would have escaped Earth’s gravity more easily when it was less massive ...Eons are the broadest category of geologic time, and we live in the Phanerozoic eon. The three eras of the Phanerozoic eon divides on the basis of characteristic assemblages of life-forms. Log in for more information. Added 8/28/2019 3:31:22 AM This answer ...Eons, eras, and periods are terms used to define major geological or biological events within Earth's geological . Click the card to flip 👆 timesclae Click the card to flip 👆 1 / 248 1 / 248 Flashcards Learn Test Match Q-Chat Created by Roman82399 Share Share ...Geologic time spans are divided into units and subunits, the largest of which are eons. Eons are divided into eras, which are further divided into periods, epochs, and ages. Geologic dating is extremely imprecise.12 May 2021 ... There are four eons recognized on the geologic timescale: the Hadean Eon (which is the oldest), Archean Eon, Proterozoic Eon, and the ...The Precambrian (4500 to 543 million years ago) is a vast period of time, nearly 4,000 million years long, that began with the formation of the Earth and culminated with the Cambrian Explosion. The Precambrian accounts for seven-eighths of our planet's history. Numerous important milestones in the development of our planet and the …Fossils are fundamental to the geologic time scale. The names of most of the eons and eras end in zoic, because these time intervals are often recognized on the basis of animal life. Rocks formed during the Proterozoic Eon may have fossils of relative simple organisms, such as bacteria, algae, and wormlike animals. Dec 17, 2013 · The Precambrian Supereon is divided into three Precambrian eons: the Hadean (4500-3950 Ma), Archean (4000-2500 Ma) and Proterozoic (2500-541.0 ± 1.0 Ma). See Timetable of the Precambrian. Proterozoic: this eon refers to the time from the lower Cambrian boundary, 541.0 ± 1.0 Ma, back through 2500 Ma. As originally used, it was a synonym for ... Just as eons are subdivided into eras, eras are subdivided into units of time called periods. The most well known of all geological periods is the Jurassic period of the Mesozoic era (the movie Jurassic Park, of course, has something to do with that). The Paleozoic era is divided into six periods.Study with Quizlet and memorize flashcards containing terms like The oldest fossils usually _____. See Concept 25.2 (Page 528) are found above younger fossils contain more radioactive isotopes than younger fossils are found in sediments formed during the Cenozoic era have the longest half-lives are found in the deepest strata, A paleontologist finds a …Study with Quizlet and memorize flashcards containing terms like The study of fossil remains and other clues to past life on Earth is referred to as, The age of the Earth is approximately ______ years., The ______ is divided into a series of eons and eras, which are further divided into periods and epochs. and more.The Geological Time Scale – not the easiest thing to remember, but these short mnemonics will help!The mnemonics in this video helps us learn the names of th...EON ERA BDY. AGES (Ma) 1000 1200 1800 2050 2300 1400 1600 2500 2800 3200 3600 4000 541 635 720 PERIOD EDIACARAN CRYOGENIAN TONIAN STENIAN ECTASIAN CALYMMIAN STATHERIAN OROSIRIAN RHYACIAN SIDERIAN NEOPRO- 260 ...Sep 23, 2023 · Geologists divide the lifespan of Earth into a total of 4 eons. From origin to now, Earth’s 4 eons are the Hadean, Archean, Proterozoic and Phanerozoic Eon. The Hadean, Archean and Proterozoic eons are sometimes grouped as the Precambrian Eon. Eras. Eras are divisions of geologic time shorter than eons but longer than periods. Periods, eras and eons are some of the units used to describe sections of the Earth’s history but where these begin and end are based on a very subjective reading of the rock record. The names ...Evolution Speeds Up. Towards the end of the Precambrian Time period, much more diversity evolved. The earth was undergoing somewhat rapid climate changes, going from completely frozen over to mild to tropical and back to freezing. The species that were able to adapt to these wild fluctuations in climate survived and flourished.geological eons and eras Learn with flashcards, games, and more — for free. During the Archean Eon, which spanned from approximately 4 billion to 2.5 billion years ago, significant geological and biological events unfolded on Earth. Notably, this eon witnessed the formation of the first continents, the development of Earth’s early atmosphere, and the emergence of life in the form of simple, single-celled organisms ...In the Geologic Time Scale, time is generally divided on the basis of the earth's biotic composition, with the Phanerozoic Eon (i.e. the Paleozoic, Mesozoic and Cenozoic Eras) representing the period of Earth's history with advanced life forms, and the Pre Cambrian (or Proterozoic and Hadean Eras) representing the period before advanced life.Precambrian - Ancient Life, Fossils, Eons: Precambrian rocks were originally defined to predate the Cambrian Period and therefore all life, although the term Proterozoic was later coined from the Greek for “early life.” It is now known that Precambrian rocks contain evidence of the very beginnings of life on Earth—which, based on the age of the rocks …The lower clock is our previous version. It does not include the Phanerozoic Eon and some of the times listed for the Eons and Eras are just a bit out of date. The most significant change is the Hadean/Archean boundary. Scientists are finding new evidence of life farther back in time. The result is a shorter Hadean Eon and a longer Archean.8 Jul 2018 ... Nowadays, and speaking very generally, geological time is divided first into four great chunks known as eras: Precambrian, Paleozoic (from ...true. The tectonic forces that shaped Earth's continents no longer have any impact on Earth's features. false. Dinosaurs' skeletons can be distinguished from those of other reptiles by the structure of the hips and legs. true. The timeline correctly shows the order of time periods in the Mesozoic Era. true.You might want to start sending your packages in September. While we slog through the dog days of summer, the holiday season seems like it’s eons away. However, if you plan on sending holiday packages through the U.S. Postal Service this wi...The Phanerozoic Eon covers 541 million years and includes three major geological eras: the Paleozoic, Mesozoic and, Cenozoic. Three definitions for Eon are: 1. An indefinitely long period of time ...13 Apr 2022 ... Commonly, these time periods are refered to as "eras". But, geologically speaking, this isn't entirely correct. Let's have a closer look.Greeting card representing the evolution of organisms, with correlation to geologic eras. DEA / Universal Images Group / Science Museum Group.Precambrian, period of time extending from about 4.6 billion years ago (the point at which Earth began to form) to the beginning of the Cambrian Period, 541 million years ago. The Precambrian encompasses the Archean and Proterozoic eons, which are formal geologic intervals that lasted from 4 billion to about 541 million years ago, and the ...Q. Which of the following is not an eon of geologic time? answer choices. Hadean.Mesozoic; Paleozoic; Precambrian. MATERIALS: Internet; time chart. Students use the internet to discover geologic time.Cretaceous Period. During this period, oceans formed as land shifted and broke out of one big supercontinent into smaller ones. Continents were on the move in the Cretaceous, busy remodeling the ...Cambrian Period, earliest time division of the Paleozoic Era and Phanerozoic Eon, lasting from 538.8 million to 485.4 million years ago. The Cambrian System, named by English geologist Adam Sedgwick for slaty rocks in southern Wales and southwestern England, contains the earliest record of abundant and varied life-forms.How many subdivisions there are within each eon and era varies from source to source. Some sources say that eons are divided equally, while others claim that the Paleozoic era is shorter than the Mesozoic era, for example. There is no definitive answer to this ...Identify the eons and eras described. School subject: History (1061782) Main content: Geologic Time Scale (1284362)Phanerozoic Eon: Paleozoic Era The trilobites had a hard exoskeleton, and were an early arthropod, the same group that includes modern insects, crustaceans, and arachnids. The Phanerozoic Eon is the most recent, 541 million years ago to today, and means “visible life” because the Phanerozoic rock record is marked by an abundance of fossils.called eons, eras, periods, epochs, and ages. These units are classified based on Earth’s rock layers, or strata, and the fossils found within them. From examining these fossils, scientists know that certain organisms are characteristic of certain parts of ...Jan 31, 2019 · Towards the end of the Precambrian Time period, much more diversity evolved. The earth was undergoing somewhat rapid climate changes, going from completely frozen over to mild to tropical and back to freezing. The species that were able to adapt to these wild fluctuations in climate survived and flourished. The first protozoa appeared followed ... Archean Eon (4600 million) The oldest eon of Earth's history. Proterzoic Eon (2500 million) Second oldest eon of Earth's history. Phanerozoic Eon (545-present) The most recent eon, an interval of time from 542 Ma to the present. Paleozoic Era. Eons are made up of eras, divisions that span time periods of tens to hundreds of millions of years. The three major eras are the Paleozoic, the Mesozoic, and the Cenozoic.This exhibit was researched, written and designed by Richard Paselk, Curator Emeritus.A Timeline of the Eons’s, Era’s, & PeriodsThe development of life over the last 3,700 million years of the Earth's history is one of the great stories told by modern science. During most of this time living things left only traces to indicate their existence.28 Oct 2020 ... Find an answer to your question Explain the relationships among eons, eras, epochs, and periods of the geologic time scale.The period is the basic unit of geological time in which a single type of rock system is formed. Two or more periods comprise a geological Era. Two or more Eras form an Eon, the largest division of geologic time. Some periods are divided into epochs. The major periods in the geologic history of the Earth are (mya=million years ago): EON.At a finer level, each of those eons is divided up into intervals that we call eras. So the Phanerozoic eon is divided up into the Paleozoic, meaning old life; Mesozoic, meaning middle life; and the Cenozoic, meaning young life. And each of those eras in turn is divided up into periods with names like Cretaceous and Ordovician and Cambrian. Geologic time, the extensive interval of time occupied by the geologic history of Earth. Formal geologic time begins with the Archean …Geologic time, the extensive interval of time occupied by the geologic history of Earth. Formal geologic time begins with the Archean …Era, a very long span of geological time; in formal usage, the second longest portion of geologic time after an eon. Ten eras are recognized by the International Union of Geological Sciences. An era is composed of one or more geological periods. The stratigraphic, or rock, term that corresponds to ‘era’ is ‘erathem.’The four great epochs in Hinduism are Satya Yuga, Treta Yuga, Dwapar Yuga, and Kali Yuga. Satya Yug or the Age of Truth is said to last for 4,000 divine years, Treta Yuga for 3,000, Dwapara Yug for 2,000 and Kali Yuga will last for 1,000 divine years—a divine year equalling 432,000 earthly years. Hindu tradition holds that three of …As of April 2022 there are currently ten defined eras/erathems, namely the Eoarchean, Paleoarchean, Mesoarchean, Neoarchean, Paleoproterozoic, Mesoproterozoic, Neoproterozoic, Paleozoic, Mesozoic and Cenozoic, with none from the Hadean eon. A period is a major rank below an era and above an epoch.Video transcript. The Earth is now starting to get closer to being hospitable to people like us or animals like us. In the last video, we saw during the Proterozoic Eon, oxygen began to accumulate in the atmosphere. This actually caused this first snowball Earth and this mass extinction of all the anaerobic species.geological eons and eras Learn with flashcards, games, and more — for free.Geologic Time Scale. A record of Earth's history from its origin 4.6 billion years ago (BYA) to the present. This history is divided into blocks of time distinguished by geologic and evolutionary events. This allows scientists to correlate the geologic events, environmental changes and development of life-forms that are preserved in the fossil ...Eon, Long span of geologic time. In formal usage, eons are the longest portions of geologic time (eras are the second-longest). Three eons are recognized: the Phanerozoic Eon (dating from the present back to the beginning of the Cambrian Period), the Proterozoic Eon, and the Archean Eon. Eras are divisions of geologic time shorter than eons but longer than periods. In terms of geochronological units, there are 10 defined eras that generally span several hundred million years. For example, the Paleozoic , Mesozoic , and Cenozoic eras are within the Phanerozoic Eon.Phanerozoic Eon 542 mya—present Cenozoic Era 65 mya—present Neogene Period 23 mya—present. Holocene Epoch 8000 ya—present. Pleistocene Epoch 1.8 mya—8000ya. Pliocene Epoch 5.3 mya—1.8 mya. Miocene Epoch 23 mya—5.3 mya Paleogene Period 65 mya—23 mya. Oligocene Epoch 34 mya—23 mya. Eocene Epoch 56 mya—34 mya4 major eras in Earth’s history Precambrian 4.5 bya-540 mya Paleozoic 540mya- 250 mya Mesozoic 250 mya- 65 mya Cenozoic 65 mya-present. Longest Era- spans about 4 billion years or 89% of Earth’s total history Lots of volcanism creating Earth’s crust Some very simple organisms- bacteria, algae, protozoa Oldest Precambrian rocks …During its matter-dominated era, the expansion of the universe had begun to slow down, as gravity reined in the initial outward expansion. But from about 9.8 billion years of cosmic time, observations show that the expansion of the universe slowly stops decelerating, and gradually begins to accelerate again, instead.Study with Quizlet and memorize flashcards containing terms like The age of the earth is approximately _____ years, _____ is divided into a series of eons and eras, which are further divided into periods and epochs (mass extinctions and major biological events), The deep-water trench that has separated the islands of Borneo and Sulawesi in the Malay Archipelago (Indonesia) preventing migration ...An "eon" is the largest interval of hundreds million years ago. It is also classified as a long period of geographic time. Eons are subdivided into "eras". Eons are divided into smaller time intervals known as eras. In the frame, the Phanerozoic is divided into three eras: Cenozoic, Mesozoic and Paleozoic. Very significant events in Earth's ...Fossils, such as Tiktaalik, can provide information regarding. the evolution of organisms. What time period of the geologic timescale spans the most years. Proterozoic eon. Anatomical structures, fossils, and molecular data all provide evidence of. evolution. The figure illustrates how a (n) ______ fossil forms. Geology Geologic Time Scale: Major Eons, Eras, Periods and Epochs Table of content The geologic time scale is a system of chronological classification used to organize and …The Precambrian was the first super eon of Earth’s history. This division of time — about seven-eighths of Earth's history — lasted from the first formation of the planet (about 4.6 ...For this journal page, you are constructing a timeline that shows the relative lengths of geologic time. Include the order and relative lengths of the Precambrian Supereon and its three Eons (Hadean, Archaen, Proterozoic) and the Phanaerozoic Eon and its three Eras (Paleozoic, Mesozoic, and Cenozoic). The Precambrian will be ­very long ... This chapter will cover briefly the origin of the universe and the 4.6 billion year history of Earth. This Earth history will focus on the major physical and biological events in each eon and Era. 8.1: Origin of the Universe. The mysterious details of events prior to and during the origin of the universe are subject to great scientific debate.Geologic time, the extensive interval of time occupied by the geologic history of Earth. Formal geologic time begins with the Archean Eon (4.0 billion to 2.5 billion years ago) and continues to the present day. Modern geologic time scales also include the Hadean Eon (4.6 billion to 4.0 billion years ago).

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eons and eras

The lower clock is our previous version. It does not include the Phanerozoic Eon and some of the times listed for the Eons and Eras are just a bit out of date. The most significant change is the Hadean/Archean boundary. Scientists are finding new evidence of life farther back in time. The result is a shorter Hadean Eon and a longer Archean.Eons of geological time are subdivided into eras, which are the second-longest units of geological time. The Phanerozoic eon is divided into three eras: the Paleozoic, Mesozoic, and Cenozoic. The three eras of the Phanerozoic eon.4500-1500 million years ago. This is the first Era to have geologic record. In this early stage of the earth, the surface changes from molten to rock. The continental plates also formed during this timeline. The atmosphere of the earth is made up of 75% nitrogen & 15% carbon Dioxide. These are known as prokaryotic cells.Apr 22, 2016 · Eons, eras, periods and epochs. (Image credit: by Karl Tate, Infographics Artist) Live Science newsletter. Stay up to date on the latest science news by signing up for our Essentials newsletter. Standard 8-2.4: Recognize the relationship among the units—era, epoch, and period—into which the geologic time scale is divided. Eons: Longest subdivision; based on the abundance of certain fossils Eras: Next to longest subdivision; marked by major changes in the fossil record Periods: Based on types of life existing at the timeThe preceding eon, the Archaean, marks the origin of prokaryotes; the subsequent eon, the Phanerozoic, marks the colonization of land and the origin of humans. Many present-day animal phyla appeared suddenly in fossils formed 535-525 million years ago, during the Paleozoic era of the Phanerozoic eon.It is divided into eons, which are further divided into eras. Note – the string is 19 feet long, so make sure you have enough room to “spread”. One VSVS member or student volunteer will hold the string and another will hold the container and walk to the right while removing each eon and stopping when a knot is reached.Today, the geologic time scale is divided into major chunks of time called eons. Eons may be further divided into smaller chunks called eras, and each era is divided into periods. Figure 12.1 shows you what the geologic time scale looks like. We now live in the Phanerozoic eon, the Cenozoic era, and the Quarternary period. Label the Eons, Eras, and time points — Quiz Information This is an online quiz called Label the Eons, Eras, and time points You can use it as Label the Eons, Eras, and time points practice, completely free to play.Jurassic Period, second of three periods of the Mesozoic Era. Extending from 201.3 million to 145 million years ago, the Jurassic was a time of global change in the continents, oceanographic patterns, and biological systems. On land, dinosaurs and flying pterosaurs dominated, and birds made their first appearance.An eon is the largest (formal) geochronologic time unit and is the equivalent of a chronostratigraphic eonothem. As of October 2022 there are four formally defined eons/eonothems: the Hadean, Archean, Proterozoic and Phanerozoic. An era is the second largest geochronologic time unit and is the equivalent of a chronostratigraphic erathem. The period is the basic unit of geological time in which a single type of rock system is formed. Two or more periods comprise a geological Era. Two or more Eras form an Eon, the largest division of geologic time. Some periods are divided into epochs. The major periods in the geologic history of the Earth are (mya=million years ago): EON. 28 Feb 2020 ... segmented into five subgroups which are Eons, Eras, Periods, Epochs and Ages. To know more geological facts, visit https://www.gsi.gov.in # ...Eons, eras, periods and epochs. (Image credit: by Karl Tate, Infographics Artist) Live Science newsletter. Stay up to date on the latest science news by signing up for our Essentials newsletter.What are the 4 eons of the geologic time scale? Geology. For example, the entire age of the earth is divided into four eons: the Hadean Eon, the Archean Eon, the Proterozoic Eon, and the Phanerozoic Eon. These four eons are further subdivided into eras (Table 7.3)..

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