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Geologists know that potassium-40 decays to argon-40, with a half-life of 1.3 billion years. if an analysis of a feldspar crystal in a sample of granite shows that 75 percent of the potassium-40 atoms have decayed to form argon-40, what is the age of the granite

Landmasses on a flat map look distorted because

These are the abiotic factor or biotic factors that restricts the numbers, reproduction, or distribution of organisms.