27. for a fixed positive integer n2 3, let a be the nxn matrix defined as a = i-j, where i is the identity matrix and j is the n x nmatrix with all entries equa

27. For a fixed positive integer n2 3, let A be the nxn matrix defined as A = I-J, where I is the identity matrix and J is the n x nmatrix with all entries equal to 1. Which of the following statements is not true? Ma) A =A for every positive integer k (b) Trace (A) = n-1 (c) Rank (A) + Rank (- A) = n )A is invertible