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includes algal-mat deposits (stromatolites) from the Precambrian Chuar Group of the Grand Canyon Supergroup, deep in the Canyon near the river, from a time when biology was not a whole lot more diverse than algal mats.Correct Answer(s):ATable for Individual Question FeedbackPoints Earned:1.0/1.014.Geological evidence based on several radiometric techniques has provided a scientifically well-accepted age for the Earth. Represent that age of the Earth as the 100-yard length ofa football field, and any time interval can be represented 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 lasted one-half of the age of the Earth would be fifty yards.) On this scale, the time from when dinosaur extinction made space for large mammals, until today, would be represented by how far on the football field?Table for Individual Question FeedbackPoints Earned:1.0/1.015.What is accurate about the scientific results learned by counting annual layers in ice cores?
Table for Individual Question FeedbackPoints Earned:1.0/1.0Points Awarded12.00Points Missed3.00Percentage80.0%1. Which is the oldest sedimentary rock layer:Table for Individual QuestionFeedbackPoints Earned: 1.0/1.0