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Problem 2. The resistivity of aluminum at 25C has been measured to be 2.72106cm. Aluminum has a valency of 3 , a density of 2.70cm3g, and an atomic mass of 27g. (a) Estimate their drift mobility, (b) Estimate the mean free time between collisions for the conduction electrons in aluminum at 25C, (make sure that the units in your calculation are correct and consistent) (c) If the mean speed of the conduction electrons is about 2106secm, calculate the mean free path. Answer (a) the drift mobility is: (b) the mean free time between collision is: (c) the mean free path is: Calculation