In the following sentences there are italicized words or phrases, marked (A), (B), (C) and (D). Find the one italicized word or phrase that should be changed to make the sentence correct.
1. A chemical element is an aggregate of atoms, all of which have the same atomic number.
2. Therefore it is not possible to change matter into simple substances than pure elements.
3. There are 103 internationally known elements, the last 11 of which were discovered recently.
4. The 93d element, neptunium (Np), and the 94th element, plutonium (Pu), have been discovered during the development of atomic fission.
5. They are products of ninety - second element, uranium.
6. Neptunium has usually been represented as Np, and plutonium as Pu, - the subscripts specify their atomic numbers, and super-scripts – their atomic weights.
7. Neptunium and plutonium are isobars, that is, elements with the some atomic weight (239), but different atomic numbers (93 and 94).
8. The 95th and 96th elements, discovered in 1945 at the University of California, are obtained by means of cyclotron.
9. In 1946, G.T. Seaborg, the codiscoverer of these elements has announced their names.
10. The 95th element was called americium in honor of Americas.
Отредактируйте задание,пометьте, где этиА В С D.они должны быть другим шрифтом,хотя бы поставьте буквы после этих слов. Пока вижу только две ошибки. 9 вместо has announced. Надо announced. 3 were discovered -надо have been discovered.