A 2-mm-diameter electrical wire is insulated by a 2-mm-thick rubberized sheath (k 0.13 W/m K), and the wire/sheath interface is characterized by a thermal contact resistance of . The convection heat transfer coefficient at the outer surface of the sheath is 10 W/m2 K, and the temperature of the ambient air is 20 C. If the temperature of the insulation may not exceed 50 C, what is the maximum allowable electrical power that may be dissipated per unit length of the conductor