$2.$ Input Variables $(5$ points$).$ Identify five decision variables of a manufacturing system that tend to be random.

$3.$ Output Variables $(6$ points$).$ Depending on the system that you are analyzing, sometimes seeing a time$-$series graph is more useful than just seeing an average value. Why would this be the case for studying inventory at a warehouse?

$4.$ Discrete vs$.$ Continuous $(4$ points$).$ For each of the following simulation applications identify one discrete$-$ and one continuous change state variable.

a$.$ Inventory control of an oil storage and pumping facility

b$.$ Study of beverage production in a soft drink production facility