State the Pauli exclusion principle. Write the electronic configurations of `""_(24)Cr^(3+)` and `""_(27)Co^(3+)`.

Explanation

First part: N/A ,brgt Second part: `""_(24)Cr^(3+):1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)d^(3)`
`""_(27)Co^(3+):1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(6)`.