Consider a region with average surface temperature T 0 = 10 C, annual fluctuations of T

Consider a region with average surface temperature T₀ = 10 ^◦C, annual fluctuations of ΔT = 30 ^◦C, and surface soil with a ≅ 2.4 × 10⁻⁷ m²/s, k ≅ 0.3W/mK. If the local upward heat flux from geothermal sources is 80mW/m², compute the depth at which the heat flux from surface fluctuations is comparable. What is the answer if the area is geo thermally active and has a geothermal heat flux of 160mW/m²?