60. A 100-W light bulb is made from a glass sphere with a radius of 3.0 cm and athickness of 0.5 mm. It consumes 100 W of electricity and produces 95 W of heat,which is dissipated through the glass bulb. The thermal emissivity of uncoatedsmooth glass is about 0.9. The value of the Stefan-Boltzmann constant is σ = 5.67 10-8 W/m2.K4. The thermal conductivity of glass is 0.84 J/sㆍmㆍ℃. Which of thefollowing values is closest to the temperature difference (K) between the inner andouter surfaces of the glass?
(A)20.0
(B)10.0
(C)5.0
(D)2.0
(E)0.4