Determine which of the following transformations are linear transformations.
A. The transformation T defined by T ( x1 , x2 , x3) = ( x1, 0 , x3 ) .
B. The transformation T defined by T ( x1, x2, x 3 ) = ( 1 , x2, x3)
C. The transformation T defined by T (x1, x2 ) = (2x1 −3 x2, x1+ 4,5 x 2 )
D. The transformation T defined by T ( x1 , x2) = (4x 1−2x2,3 | x2 | )
E. The transformation T defined by T (x1, x2,x 3) = (x1, x2,− x3)