Final answer:
The 4th stage of labor lasts from a few minutes to half an hour and involves the expulsion of the placenta.
Step-by-step explanation:
The duration of the 4th stage of labor can vary, but it generally lasts from a few minutes to half an hour.
During this stage, the placenta is expelled after the baby has been born and the organ has completely disengaged from the uterine wall.
This stage is important for the completion of the birthing process and ensuring that the mother's body recovers fully.