Example $2$: Assembly Line Balancing

Given in the following table are the tasks necessary for the assembly of a particular product, the length of time needed to perform each task, and the operations that must be completed prior to subsequent operations.

$\backslash$table$[[$Task$,$Time $($min$),$Precedence$],[$A$,4,-],[$B$,2,$A$],[$C$,5,$B$],[$D$,5,$B$],[$E$,4,$A$],[$F$,3,$C$,$D$],[$G$,5,$F$],[$H$,2,$E$],[$I$,10,$G$,$H$]]$

Calculate the cycle time necessary to complete $40$ units of product in a day. Assume working time for a day is $400$ minutes. Then balance the line and calculate line's efficiency.