Element z has two naturally occurring isotopes. Its first isotope has a mass of 28. 0 amu and a natural abundance of 64. 24%. Its second isotope has a mass of 25. 0 amu. What is the average atomic mass of element z?

True or falsethe right to privacy is clearly written out in the constitution

Earth's atmosphere is unique among the planets and is able to support life because it contains a large amount of a) oxygen b) helium c) methane d) carbon dioxide

In the image, layer a is the topmost layer. layer c contains fossils from the precambrian era. layer b contains dinosaur fossils, and layer a contains fossils of mammals. which two statements are supported by this evidence? 1. mammals lived before the precambrian era. 2. dinosaurs and mammals existed in the precambrian era. 3. dinosaurs evolved after precambrian organisms. 4. precambrian organisms evolved after dinosaurs. 5. precambrian organisms were the first life-forms to become fossilized, according to this sample.