The average rate at which energy

is conducted outward through

the ground surface in North America is 54.0 mW/m2, and the average

thermal conductivity of the near-surface rocks is 2.50 W/m K.

Assuming a surface temperature of 10.0°C, find the temperature at

a depth of 35.0 km (near the base of the crust). Ignore the heat

generated by the presence of radioactive elements.