Draw the network diagram

$\backslash$table$[[,$Precedences and Durations for a Seven Activity Project$],[\backslash$table$[[$Duration$],[($Days$)]],$Activity,Description,Predecessor,Duration$],[$A$,$Preliminary design,$--,6],[$B$,$Evaluation of design,A$,1],[$C$,$Contract negotiation,$---,8],[$D$,$Preparation of fabrication plan,C$,5],[$E$,$Final design,$B,C,9],[$F$,$Fabrication of Product,$D,E,12],[$G$,$Shipment of Product to ownes,F$,3]]$