A 14 Geological evidence based on several radiometric techniques has provided a

A 14 geological evidence based on several radiometric

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A14.Geological evidence based on several radiometric techniques has provideda scientifically well-accepted age for the Earth. Represent that age of the Earth as the 100-yard length of a football field, and any time interval can berepresented as some distance on the field. (So something that lasted one-tenth of the age of the Earth would be ten yards, and something that lastedone-half of the age of the Earth would be fifty yards.) On this scale, how faron the football field would represent the time between the first appearance of abundant shelly creatures and today?A) Over 80 yards.B) 60 yards.C) 50 yards.D) Just over 10 yards.E) Over 90 yards.Feedback: If the 4.6 billion years of Earth history are 100 yards, then the 570 million years since the widespread appearance of shelly creatures is a bit over 10 yards. Most of our fossil record is limited to the last 10% of the planet’s history. The shells appeared “suddenly”—in a few million years, or a few inches on the football field of time.Table for Individual Question FeedbackPoints Earned:1.0/1.0D
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15.What is accurate about the scientific results learned by counting annual layers in ice cores?Table for Individual Question FeedbackPoints Earned:1.0/1.0Correct Answer(s):C
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  • Fall '07
  • ALLEY
  • Sedimentary rocks

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