physics conductivity?

Question

Two shorter cylinders with radii of 0.70 cm and a combined length of 23.00 cm are used. The upper cylinder is made of yellow brass (k = 220 W/(moC), length = 4.60 cm). The lower cylinder's composition is unknown. The temperature where the two cylinders are in thermal contact is 44.0345 oC. What is the rate of heat flow through the combined cylinders?

also, Find the thermal conductivity of the unknown substance. (In W/m/degC.)

Answer 1

You need to specify something else, like what is the temperature at the end of one of the cylinders.