The Rover $6$ is a new custom$-$designed sports car. An analysis of the task of building the Rover $6$ reveals the following list of relevant activities, their immediate predecessors, and their duration.

ACTIVITY DESCREPTION TIME$($DAYS$)$ IMMEDIATE PREDECESSOR$($S$)$

A Start $0--$

B Design $8$ A

C Order special accessories $0\mathrm{.}1$ B

D Build frame $1$ B

E Build doors $1$ B

F Attach axies, wheels, gas tank $1$ D

G Build body shell $2$ B

H Build transmission and drivetrain $3$ B

I Fit doors to bod shell $1$ G$,$E

J Build engine $4$ B

K Bench$-$test engine $2$ J

L Assemble chassis $1$ F$,$ H$,$ K

M Road$-$test chassis $0\mathrm{.}5$ L

N Paint body $2$ I

O Install wiring $1$ N

P Install interior $1\mathrm{.}5$ N

Q Accept delivery of special accessories $5$ C

R Mount body and accessories on chassis $1$ M$,$O$,$P$,$Q

S Road test car $0\mathrm{.}5$ R

T Attach exterior trim $1$ S

U Finish $0$ T

What is the critical Path and duration of the project $?$

Critial Path $=$ A$-$B$-$J$-$K$-$L$-$M$-$R$-$S$-$T$-$U

Duration length $=11$ days

Critial Path $=$ A$-$B$-$J$-$K$-$L$-$M$-$R$-$S$-$T$-$U

Duration length $=14$ days

Critial Path $=$ A$-$B$-$J$-$K$-$L$-$M$-$R$-$S$-$T$-$U

Duration length $=18$ days

Critial Path $=$ A$-$B$-$D$-$K$-$L$-$M$-$R$-$S$-$T$-$U

Duration length $=18$ days