There are 18 students in mr. alvarez’s art class. throughout the year, every student must pair up with every other student to complete a project. how many projects will be finished?
a. 149 projects
b. 153 projects
c. 171 projects
d. 135 projects

Agroup of student volunteers participates in a study designed to assess several behavioral interventions for improving output in a repetitive task. prior to the beginning of the study, all volunteers unknowingly observed, and their output is measured. at the beginning of the study, prior to any intervention, the volunteers perform the same task under the observation of a study administrator, and their overall output increases. which of the following terms describes this phenomenon? a. simpson's paradox b. hawthorne effect are d. novelty effect d. pygmalion effect e. observer-expectancy effect