$7-$ The following chart shows the material flow between departments in a factory. Use the graph$-$ based method to design a layout. Which of the following is the sequence of departments $(1$ through $5)$ selected to be placed in the layout according to graph$-$based method?$($Note: Select the two departments with highest flow between them. Then check the remaining departments to see which one has the highest total flow with the selected two departments and select it$.$ Repeat this step until one department is left, which will be the last one selected$)$From to Material flow between departments $($units$/$days$)$ Departments

$12345$

$1-1816203$

$2--242614$

$3---40$

$4----4$

$5-----$