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Ais not a compound machine. a. bolt b. shovel c. handcart (dolly) d. see-saw (teeter totter)

Automobile fuel efficiency is often measured in miles that the car can be driven per gallon of fuel (mpg). heavier cars tend to have lower fuel efficiencies (lower mpg ratings). which variable (weight or fuel efficiency) is most naturally considered the explanatory (predictor) variable in this context?

On a geologic map, if the contacts between sedimentary rock units form a bull’s-eye pattern of concentric circles, with the youngest unit in the center, the underlying structure is a(n)