Figure:
A researcher was interested in the effects of arousal and personality on individuals' GRE test performance.The personality variable he examined was individuals' level of introversion-extraversion.Based on questionnaire responses,each participant was classified as an "extravert" or an "introvert." The researcher manipulated arousal level by giving caffeine to participants prior to administering a practice GRE test.Participants were randomly assigned to a high-caffeine condition,a medium-caffeine condition,or the no-caffeine conditions.All participants then completed a practice version of the quantitative portion of the GRE.
Suppose the researcher observed the following means for each group:
-The means for the main effect of arousal level are
A)600 and 600.
B)600,600,and 600.
C)500,600,and 700.
D)The means cannot be determined in this design.

Question

Figure:
A researcher was interested in the effects of arousal and personality on individuals' GRE test performance.The personality variable he examined was individuals' level of introversion-extraversion.Based on questionnaire responses,each participant was classified as an "extravert" or an "introvert." The researcher manipulated arousal level by giving caffeine to participants prior to administering a practice GRE test.Participants were randomly assigned to a high-caffeine condition,a medium-caffeine condition,or the no-caffeine conditions.All participants then completed a practice version of the quantitative portion of the GRE.
Suppose the researcher observed the following means for each group: 
-The means for the main effect of arousal level are
A)600 and 600. 
B)600,600,and 600. 
C)500,600,and 700. 
D)The means cannot be determined in this design.

Quizplus · Accepted Answer

The Answer of Figure:
A researcher was interested in the effects of arousal and personality on individuals' GRE test performance.The personality variable he examined was individuals' level of introversion-extraversion.Based on questionnaire responses,each participant was classified as an "extravert" or an "introvert." The researcher manipulated arousal level by giving caffeine to participants prior to administering a practice GRE test.Participants were randomly assigned to a high-caffeine condition,a medium-caffeine condition,or the no-caffeine conditions.All participants then completed a practice version of the quantitative portion of the GRE.
Suppose the researcher observed the following means for each group: 
-The means for the main effect of arousal level are
A)600 and 600. 
B)600,600,and 600. 
C)500,600,and 700. 
D)The means cannot be determined in this design.

Figure: a Researcher Was Interested in the Effects of Arousal and and Personality