Q:  What is the value of the temperature derivative in this shell?

    
        dT/dr  =  - 4.37 x 10^(-5)    K/cm



  Q:  What is the temperature of the next-inner shell?


        T_new  =  T_old           +  (dT/dr) * dr

               =  4.86 x 10^4 K   +  (-4.37 x 10^(-5) K/cm) * (-7.1 x 10^7 cm)

               =  4.86 x 10^4 K   +  3.10 x 10^3 K

               =  5.17 x 10^4 K