Let ra: r2 --> r2 denote the reflection in the line 12 = xı tana (the line that makes angle a with the first coordinate axis). find the matrix of the composition rq o rg and show that this composition is a rotation. what is the angle of this rotation? what if you swap the order and consider the composition r o rq?

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