Train A leaves Paris and travels at a constant speed of 75 mph toward Pisa. At the same time. Train B leaves Pisa headed toward Paris at a constant speed of 50
mph. Let x represent time traveled in hours and let y represent miles from Paris. If
Paris and Pisa are 500 miles apart, when will the two trains pass each other?

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