-4 -2 0 5 0 0 2. Let A = 0 5 20 2 -3 7 1 (a) (8 points) Compute det A. (b) (2 points) Compute det(-A). (c) (6 points) Find one eigenvalue of A by finding a number A such that A - A4 is not invertible. Explain how you know the matrix is not invertible. (You do not have to find ALL eigenvalues of A.) (d) (6 points) Determine if it is possible to find a vector b in R4 such that Ax = b is inconsistent. Justify your answer. (e) (3 points) TRUE or FALSE: If B is an nxn matrix whose entries are real numbers, then det (BTB) > 0.