a$.$ What is the project's duration if only normal times are used?

b$.$ What is the minimum$-$cost schedule?

c$.$ What is the critical path for the minimum$-$cost schedule?

$\backslash$table$[[$Activity$,\backslash$table$[[$Normal$],[$Time$],[($days$)]],\backslash$table$[[$Nomal$],[$Cost $($$$)]],\backslash$table$[[$Crash$],[$Time$],[($days$)]],\backslash$table$[[$Crash$],[$Cost $($$$)]],\backslash$table$[[$Immediate$],[$Predecessor$($s$)]]],[$A$,6,1,000,5,1,200,-],[$B$,4,800,2,2,000,-],[$D$,3,600,2,900,$A$,$ B$],[$E$,2,1,500,1,2,000,$B$],[$F$,2,900,4,1,200,$C$,$ D$],[$G$,4,900,4,900,$E$],[$H$,4,500,2,900,$G$]]$