Secondary succession occurs following triggers such as logging, mining, wildfires, or drought. The presence of soil nutrients allows for a faster recovery. Hardwood trees Pine trees Perennials
and
grasses
Shrubs

100%sorry if i’m wronghope this good luck: )

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.

Ido not understand.