Does this cat look A. cute or B. Mean

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?

Is when a person has given their consent based on understanding the actions and facts of a study?

According to the article 13 of the articles of confederation,what percentage of votes by the states was required to ratify any amendments