$6\mathrm{.}1$ Describe and expound the specific applications for each of the below Unit Load Racking systems.

$6\mathrm{.}1\mathrm{.}1$ Cantilever Rack

$6\mathrm{.}1\mathrm{.}2$ Drive$-$In Rack

$(2)$

$6\mathrm{.}1\mathrm{.}3$ Block Stacking

$6\mathrm{.}1\mathrm{.}4$ Push$-$Back Rack

$(2)$

$6\mathrm{.}1\mathrm{.}5$ Single$-$Deep Selective Rack

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