What 1837 invention changed communications in the United States?d

This chart shows the number of soldiers killed according to two different sources. source a is a book written by university professors. source b is from a well-known historical website. in a paragraph, explain why the data presented is different, and evaluate the reliability of each source. which should be used in a school research project, and why?

How has the elimination of trade barriers affected the movement of goods among member countries of the european union? a. member countries are able to produce all the goods they need. b. goods can move freely among member countries. c. member countries no longer need to trade with countries outside the eu. d. larger countries are able to import more goods than smaller ones.

Martha participates in a research study in order to receive extra credit for her psychology class. when she arrives in the research office she is given a can of what looks and tastes like beer, but which actually contains no alcohol. in the adjoining room martha's classmate karen is also participating in the study. karen receives a can of alcoholic beer. if the experiment was designed to test the effects of alcohol on concentration, then who is exposed to the independent variable?