A service process is described by the above flowchart. After going through workstation A$,$ an order needs to be processed by one of the three lines, B$1-$C$1-$D$1,$ B$2-$C$2-$D$2,$ or B$3-$C$3-$D$3($in other words, they are substitutable$).$ Finally, all orders need to go through workstation E$.$ The capacities of the individual workstations are given as follows:Workstation A has a capacity of $2$ orders$/$hourWorkstation B$1,$ B$2,$ and B$3$ have the same capacity of $3$ orders$/$hourWorkstation C$1,$ C$2,$ and C$3$ have the same capacity of $1$ orders$/$hourWorkstation D$1,$ D$2,$ and D$3$ have the same capacity of $3$ orders$/$hourWorkstation E has a capacity of $6$ orders$/$hourWhat is capacity of the service process in orders$/$hour$?$