HELP
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Write the symbol for every chemical element that has atomic number greater than 3 and atomic mass less than 12.0 u.

Remember to use the proper number of significant figures and leading zeros in all calculations.gelatin has a density of 1.27 g/cm³. if you have a blob of gelatin dessert that fills a 2.0 liter bottle, what is its mass? 2540 g2500 g3.9 x 10-43.937x 10-4

How are isotopes of the same chemical element alike? how are they different?