Question 1 (1 point) 1 2 3 Let A = 4 5 6 . Then 5 79 O A-1 does not exist. O A -1 = -2 -5 -8 3 6 -9 O 2 Co A = -4 -5 -6 5 -7 O 1 1/2 1/3 A-1 = 1/4 1/5 1/6 [1/5 1/7 1/9] O 1 4 7 -1 = 2 5 8 3 69 Question 2 (1 point) Let A be an m X 71 matrix. The equation Ax = b has a solution for every b in RT if and only if there is a pivot in every row of A. O True FalseQuestion 3 (1 point) 1 .2 1 Let A = [-1 5 0 1 -4 O O A-1 does not exist. O 1 4 1 Al = 01 1 2 3 O 0 4 5 A-1 = 01 1 1 2 3 O 0 4 5 A- = 1 1 1 -1 2 3 O None of the other four. Question 4 (1 point) A square matrix is invertible if its columns are linearly dependent. True O False Question 5 (1 point) 1 -1 The matrix 0 0 3 is invertible. 1 4 True O False