An array of power transistors, dissipating 6 W ofpower each, are to be cooled by mounting them on a 25-cm *25-cm-square aluminum plate and blowing air at 35°C overthe plate with a fan at a velocity of 4 m/s. The average temperatureof the plate is not to exceed 65°C. Assuming theheat transfer from the back side of the plate to be negligibleand disregarding radiation, determine the number of transistorsthat can be placed on this plate.

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