A Styrofoam cooler has a surface area of 2,700 cm^2 and a wall thickness of 3.0 cm. Styrofoam has a coefficient of thermal conductivity of 0.01 W/mC. A 2.0 kg block of ice is placed inside the cooler that has a temperature inside of 2.0 degrees C. If the heat of fusion for ice is 333.7 kJ/kg and the temperature outside is 35.0 degrees C, then how long will the ice last?

Answer is 62 hours

Equation for thermal conduction :
Q = k A (∆T / L)t

Any input would be helpful, thanks!