Which of the following is not a way the transcontinental railroad changed the great plains?

Dr. redbull conducts a study to determine whether her new energy drink children perform better on spelling tests. she randomly assigns children to one of two groups: group 1 receives her energy drink and group 2 receives water. she then gives both groups a spelling test and compares the results. which of the following is true about this study? a. group 1 is the dependent variable and group 2 is the independent variable. b. this is a correlational study. c. group 2 is the experimental group. d. the independent variable is the type of drink the children receive.

In the context of c. h. cooley's theory of groups, identify each attribute as either belonging to a primary group or a secondary group.

Crops grew well in mesopotamia because a. the land was in mountainous areas. b. farmland was fertile and water was nearby. c. the area was near the ocean water supply. d. the area received adequate rainfall. select the best answer from the choices provided a b c d