Respuesta :

Answer:

Cu

Explanation:

The sublevel notation is

    1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁹

The element is unknown;

    To find the element, sum the superscipts because the indicate the electrons;

2 + 2 + 6 + 2 + 6 + 2 + 9 = 29

The element with 29 electrons is copper