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4. a spring scale is constructed so that each 0.10-n increment is separated by 0.50 cm. what spring constant is necessary for the scale to be accurate? -1.0n/cm -0.10n/cm -9.8 n/cm -0.20n/cm

Given that de, df, and ef are midsegments of △abc, and de=3.2 feet, ef=4 feet, and df=2.4 feet, the perimeter of △abc is .

Which of the following describes the symmetry of the graph of y = x3?