To solve 2x+9=21, what is the first step?

If 1 is divided by the sum of y& 4. the result is equal to 3 divided by 4 .find the value of m?

An elevator travels 310 feet in 10 seconds. at that speed, how far can't his elevator travel in 12 seconds?

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