Energy Balance Equation

My question was question 3. The energy Balance Equation is used to calculate the average temperature of the Earth in Kelvins. First I solved it symbolically then with numbers. 

 S/4 (1-A)/εσ = εσTe^4/εσ  –>
 
1/4^[S/4εσ(1-A)] = [Te^4]^1/4  –>
 
[S/4εσ(1-A)]^1/4=Te

S=Solar Constant=1370 w/m^2/k^4

A=Albedo=3

ε=Epsilon=1

σ=sigma=5.67×10^-8 

[(1370)(1-.3)/4(1)(5.67x10^-8)]^1/4 = Te  –>

Te = 255 Kelvins