$(15$ points$)$ There are $11$ assembly tasks for a product. The task times and predecessor relationships are given in the following table.

$\backslash$table$[[$Task$,$A$,$B$,$C$,$D$,$E$,$F$,$G$,$H$,$I,J$,$K$],[$Task Time $($sec$.),40,25,31,25,30,34,35,5,15,40,35],[$Immediate Predecessor$($s$),-,$A$,$A$,$A$,$B$,$ C$,$D$,$E$,$F$,$E$,$ H$,$H$,$G$,$ I, J$]]$

Suppose that the company wants to assemble $48$ units every one hour.

Draw the precedence diagram of the tasks, and then determine the assignment of the tasks to the first two workstations using the Ranked Positional Weight method $($In case of ties, give the priority to the task with the highest positional weight$).$