Donald has a spherical ornament. he knows that the surface area of the ornament is equal to 4 times the product of and the square of the radius of the ornament. donald measured the radius of the ornament and found it to be 5 inches. if a represents the surface area of the ornament, then which of the following equations can be used to calculate the surface area of the ornament?

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