Write the electronic configuration of the elements with the atomic number `61,91,101` and `109`.

Explanation

`Z=61` (promethium, Pm) `=4f^(5)5d^(0)6s^(2)`
`Z=91` (Protactium Pa) `=5f^(2)6d^(1)7s^(2)`
`Z=101` (Mendelevium Md) `=5f^(13)6d^(0)7s^(2)`
`Z=109` (Meitnerium Mt) `=5f^(14)6d^(7)7s^(2)`