The heat flow by conduction through a cylindrical object whose inner diameter, $d_{i}=20 \mathrm{~mm}$, outer diameter, $d_{o}=30 \mathrm{~mm}$, and length, $L=1$ meter, is given theoretically by:

\[q=\frac{T_{\text {high }}-T_{\text {low }}}{\frac{\ln \left(d_{\text {out }} / d_{\text {in }}\right)}{2 \pi k L}}\]

Engineers want to use this formula determine the thermal conductivity of the cylinder material. The data are shown in the table. Determine from this data what the thermal conductivity of the cylinder material is.

Temperature Difference (K)	Heat Flow (W)
10	1628.36
15	2458.2
20	2818.4
25	3838.37
30	4511.55
35	5143.88
40	6128.46
45	7197.65
50	7997.66
55	8432.74
60	9038.2