What would you call a political system that is only meant to last for a short time

Completar fill in the blanks with words from the list based on the panorama cultural video.

Ato z on the bun timeline show where the events listed a through g board blow fit on the timeline

Chen's research team randomly assigned some newborns and their mothers either to a breastfeeding promotion group (where breastfeeding was encouraged, but not required) or to a normal pediatric care group (where breastfeeding was neither encouraged nor discouraged). which research method did they use?