Determine Which of the indicated column vectors k are eigenvectors of the given matrix A by reporting the corresponding eigenvalue (if a column vector k is not an eigenvector of A, then enter none) .
a) k = (10) ( 10) ; Eigenvalue: 3
b) k = (01) ( 01) ; Eigenvalue: 2
c) k = (11) ( 11 ) ; None
d) k = (23) ( 23) ; None