Which equations are true?

there is more than one correct answer choice. select all that apply.

14+21w=7(2+3w)

9(8h−3)=72h−27

3⋅6f+3⋅11=18f−33

4⋅5m+4⋅7=20m+47

49r+35=7(7r+35)

5⋅2+5⋅3t=10+15t

Determine the number of girls in a math class with 87 boys if there are 25 girls for every 75 boys

Find the volume of the solid bounded by the plane z=0 and the paraboloid z=1-x^2 –y^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