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17-53 Consider a 15-cm 20cm epoxy glass laminate (k=0.17W/mC) whose thickness is 0.13cm. In order to reduce the thermal resistance across its thickness, cylindrical copper fillings (k=386W/mC) of 0.05cm diameter are to be planted throughout the board, with a center-tocenter distance of 0.15cm. Determine the new value of the thermal resistance of the epoxy board for heat conduction across its thickness as a result of this modification. Answer: 0.00128C/W