In a within-subjects study that extends over a relatively long time, it is possible that there will be systematic changes in the participants’ skills or knowledge during the time of the study. when these changes influence the participants’ scores, causing scores at the end of the study to be different from scores at the beginning, the effect is called

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.

As nina and erin were eating lunch in the central high school student cafeteria, they were discussing the news coverage about the girls' athletic coach being arrested for selling steroids to student athletes. "i think the guy just did it because they don't pay teachers enough money," nina suggested. "i bet the guy had some other kind of drug addiction he was trying to pay for," erin countered. nina and erin's ideas about the cause of the coach's drug-selling behavior are examples of:

In the 1800s, dorothea dix worked to improve conditions ina.)prisons and hospitals.b.)mills and factories.c.)utopian communities.d.)public schools