Linear Algebra Problem

 

0 0 0 1/2
1/3 0 0 0
1/3 1/2 0 1/2
1/3 1/2 0 0

 

 

Please find the largest positive eigenvalue and the corresponding nonnegative eigenvector for this 4×4 matrix

 

I need this done quickly, only accept this problem if you can start it now please.