# Thermodynamics Question heat through a wall

I'm stuck on this Thermo question dealing with heat transfer through a "plain wall"

They give us the area of the transfer A = 1 m^2
They give us the thickness of the wall L = .2 m
and they give us the rate of steady state energy transfer rate Qx = .15 kW

They then ask, if the temperature distribution is linear, what is the temperature difference across the wall in K.

I'm not sure how to get going on this one. Because they give actual numbers, I'm sure they want a real value for the number of Kalvins difference between the temperatures. I'm assuming they want me to use Fourier's Law here, but they don't give enough info to solve for (T2 - T1) directly. They don't give the value for the thermal conductivity of the wall, unless there is some standard value I'm supposed to use for a "plain wall". I seem to remember there was some kind of algebraic trick that I used to use to solve similar problems in physics, but the details escape my memory at the moment. If someone could get me started with this problem or give me hint to jog my memory, I'd appreciate it.