A plastic sleeve of outer radius ro = 1mm covers a wire (radius r = 0.5 m) carrying electric current. Thermal conductivity of the plastic is 0.15 W/m-K. The heat transfer coefficient on the outer surface of the sleeve exposed to air is 25 W/m2-K. Due to the addition of the plastic cover, the heat transfer from the wire to be ambient will
(a) increase (b) remain the same
(c) decrease (d) be zero