Suppose that A, B, C, D, and E are matrices with the following sizes: A B C D E (1 X 2) (1 X 6) (6X 2) (26) (2X1) Determine whether the matrix expression AB is defined. Enter the size of the resulting matrix (enter 'NA' in each box if undefined). AE is a ( X(1 X2) (1X 6) (6X 2) (2x6) (2X Determine whether the matrix expression AE V enter 'N Matrix expression is not defined Matrix expression is defined. X eTextbook and Media