I Place a 600-G Ice Cube (Initially at 0°C)in a Styrofoam

Multiple Choice

I place a 600-g ice cube (initially at 0°C) in a Styrofoam box with wall thickness 1.8 cm and total surface area 700 cm².If the air surrounding the box is at 25°C and after 6 hours the ice is completely melted,what is the conductivity of the Styrofoam material? (L_f = 80 cal/g)

A) 7.2 × 10−⁵ cal/s⋅cm⋅°C
B) 2.7 × 10−⁶ cal/s⋅cm⋅°C
C) 1.7 × 10−² cal/s⋅cm⋅°C
D) 2.4 × 10−⁴ cal/s⋅cm⋅°C
E) 9.4 × 10−⁴ cal/s⋅cm⋅°C