$Z = \sum (0, 2, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14)$
$Z = \prod (1, 3, 7, 15)$

Multiplexer type 0

Multiplexer type 1

a	b	c	d	Z	Z
0	0	0	0	1
0	0	0	1	0	~d
0	0	1	0	1
0	0	1	1	0	~d
0	1	0	0	1
0	1	0	1	1	1
0	1	1	0	1
0	1	1	1	0	~d
1	0	0	0	1
1	0	0	1	1	1
1	0	1	0	1
1	0	1	1	1	1
1	1	0	0	1
1	1	0	1	1	1
1	1	1	0	1
1	1	1	1	0	~d

Demux-mux

K-map

$x_3 x_2$ \ $x_1 x_0$	00	01	11	10	Z
00	1	0	0	1	$x_0$
01	1	1	0	1	$\overline{x_1} * \overline{x_0}$
11	1	1	0	1	$\overline{x_1} * \overline{x_0}$
10	1	1	1	1	$1$