Define the term economic system. And pls answer my other question

Ano po ung effects ng labor of migration sa community ninyo ano po yung social and economic impacts nun

Plz me match the correct text in each cell to identify the contributions to the war effort of the three facilities listed. 1. built b-29s, putting hundreds of the war's most advanced aircraft into service 2. large civilian workforce transported soldiers and goods to the two war fronts; built "liberty ships" to move men and supplies across the ocean 3. trained new recruits, held prisoners of war, repaired damaged aircraft, prepared thousands of soldiers for combat bell bomber plant military bases brunswick

The authors of the paper "fudging the numbers: distributing chocolate influences student evaluations of an undergraduate course"† carried out a study to see if events unrelated to an undergraduate course could affect student evaluations. students enrolled in statistics courses taught by the same instructor participated in the study. all students attended the same lectures and one of six discussion sections that met once a week. at the end of the course, the researchers chose three of the discussion sections to be the "chocolate group." students in these three sections were offered chocolate prior to having them fill out course evaluations. students in the other three sections were not offered chocolate. the researchers concluded that "overall, students offered chocolate gave more positive evaluations than students not offered chocolate." indicate whether the study is an observational study or an experiment. give a brief explanation for your choice.