They all have different compositions of protons, neutrons, and electrons. This causes variety and makes atoms different so they can make up different substances
Nerve cells release neurotransmitters across gaps and secretion of proteins and wastes: it’s Exocytosis
Answer: A, the sun creates it's own light.
Explanation: <em>The moon can't create it's own light, so the sun shines on the moon and it </em><em>reflects</em><em>, or "bounces" off. The sun is able to produce it's light by </em><em>fusion,</em><em> which also creates heat. </em>
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The answer would be combined statistical area. This is made of metropolitan and micropolitan statistical area which would be located in the United States as well as Puerto Rico that demonstrate both economic as well as social linkage.Hope this is the right answer.