I NEED HELP PLS ANSWER THIS WITH AN EXPLANATION TOO IM NEW AND I CAN MARK FOR BRAINLIEST

Which of the following parabolas opens down?

What rule describes a dilation with a scale factor of 4 and the center of dilation at the origin?

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