#### Answer

$p_{2x}~$ > $~p_{1x} = p_{3x} = p_{5x}~$ > $p_{4x}$

#### Work Step by Step

In general, momentum $p = mv$
We can find the momentum of block 1.
$p_{1x} = m~v_x$
$p_{1x} = (0.020~kg)(1~m/s)$
$p_{1x} = 0.020~kg~m/s$
We can find the momentum of block 2.
$p_{2x} = m~v_x$
$p_{2x} = (0.020~kg)(2~m/s)$
$p_{2x} = 0.040~kg~m/s$
We can find the momentum of block 3.
$p_{3x} = m~v_x$
$p_{3x} = (0.010~kg)(2~m/s)$
$p_{3x} = 0.020~kg~m/s$
We can find the momentum of block 4.
$p_{4x} = m~v_x$
$p_{4x} = (0.010~kg)(1~m/s)$
$p_{4x} = 0.010~kg~m/s$
We can find the momentum of block 5.
$p_{5x} = m~v_x$
$p_{5x} = (0.20~kg)(0.1~m/s)$
$p_{5x} = 0.020~kg~m/s$
We can rank the momenta in order from largest to smallest.
$p_{2x}~$ > $~p_{1x} = p_{3x} = p_{5x}~$ > $p_{4x}$