Question 4520
  Proof: If B = EA, where E is a matrix of an elementary row (column) operation,
        then transpose of B, B^T = (EA)^T = A^TE^T .
        Since the transpose of a row(column) operation is a column(row) operation.
        we see that E^T will be a matrix of an elementary column (row) operation,  
        B transpose can be obtained from A transpose by the corresponding elementary column (row) operation.
 
 Kenny