A Camper Carries Her Drinks in an Ice Chest Made

Multiple Choice

A camper carries her drinks in an ice chest made of styrofoam. The chest is 40 cm × 45 cm × 70 cm, and the walls and lid are 2.5 cm thick. The contents of the chest are ice, water, cans of soft drinks, and other food, all of which are in thermal equilibrium with the ice water. The temperature just outside the ice chest is 35°C. What is the rate of heat flow through the walls of the box? The thermal conductivity of styrofoam is 0.010 W/(m·K) .

A) 14 W
B) 16 W
C) 18 W
D) 20 W
E) 22 W