187. A tank contains liquid nitrogen at -190°C is suspended in a vacuum shell by three stainless

steel rods of 0.80 cm in diameter and 3 meters long with a thermal conductivity of 16.3 W/m2

-

°C. If the ambient air outside the vacuum shell is 15°C, calculate the magnitude of the

conductive heat flow in watts along the support rods.

A. 0.168 B. 0.0587

C. 0.182 D. 0.176