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The table below gives the predecessor activities, as well as the optimistic, most likely, and pessimistic times, for the activities of a project.

$\backslash$table$[[$Activity$,$Predecessor,Optimistic,Likely,Pessimistic$],[$A$,-,4,6,10],[$B$,$A$,2,5,8],[$C$,$A$,6,7,9],[$D$,$B$,3,9,20],[$E$,$C$,7,9,11],[$F$,$D$,$E$,7,11,19]]$

Given this information, the probability that the project will be completed by the $28$ th day