A Slab of Insulation Is Made of Three Layers,as Drawing

Multiple Choice

A slab of insulation is made of three layers,as Drawing I indicates.Each of the layers A,B,and C has the same thickness,but a different thermal conductivity.Heat flows through the slab,and the temperatures are as shown.What are the temperatures T₁ and T₂ in Drawing II where the layers are arranged in a different order?

A) T₁ = 230 °C and T₂ = 170 °C
B) T₁ = 200 °C and T₂ = 180 °C
C) T₁ = 220 °C and T₂ = 160 °C
D) T₁ = 180 °C and T₂ = 160 °C
E) T₁ = 210 °C and T₂ = 190 °C