Problem $2$: $(20$ points$)$

The work elements precedence requirements and production times to assemble a finished product are shown below

$\backslash$table$[[$Task$,$A$,$B$,$C$,$D$,$E$,$F$,$G$,$H$,$I$],[$Predecessor$($s$),-,-,$A$,$ B$,-,-,$C$,$ D$,$C$,$ E$,$ F$,$F$,$ G$,$D$],[$Time$($mn$),0\mathrm{.}35,0\mathrm{.}35,0\mathrm{.}7,0\mathrm{.}5,0\mathrm{.}5,0\mathrm{.}2,0\mathrm{.}2,0\mathrm{.}5,0\mathrm{.}1]]$

a$)$ Construct a precedence diagram of the assembly process $(5$ points$)$