If fred travels 135 miles in 3 hours at a rate of 45 mi/hr, find the rate at which he travels to cover a distance of 189 miles in 3.5 hours.

Which expression is equivalent to 64 - 9x^2?

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

2f(x)= x+3 if 4 < x < 8 2x if x 28 2