(a) The given row operations, when performed on matrix A, result in the given matrix B. Find the determinant of A and decide if A is invertible:
(1/2)R1 + R1, 5R1 + R2, ~R2, ~1R3, AR2 + R3 - R3 - 1
(b) Suppose A and B are n X n matrices with det(A) = 3 and det(B) = -2. Find the determinant (if possible) of the matrix 5A^2(B^-1)^3BT.