A solid, truncated cone serves as a support for a system that maintains the top (truncated) face of the cone at a temperature T" while the base of the cone is at a temperature T₂ < T₁.

The thermal conductivity of the solid depends on temperature according to the relation k = k_o - aT, where a is a positive constant, and the sides of the cone are well insulated. Do the following quantities increase, decrease, or remain the same with increasing x: the heat transfer rate q_x, the heat flux q”_x, the thermal conductivity k, and the temperature gradient dT/dx?

- T,, A1 -T2 < T1 A, > A1