Define "Critical path", "Slack time", "Resource Levelling" and "Dummy activity" with reference to PERT and CPM$.$

An architect has been awarded a contract to prepare plans for an urban renewal project. The job consists of the following activities and their estimated value. Draw a critical path arrow diagram for this project, indicate the critical path and calculate the total slack and free slack for each activity.

Job

Description

Predecessor

Expected time in days

A

Prepare preliminary sketches

NA

$2$

B

Outline specifications

NA

$1$

C

Prepare drawings

A

$3$

D

Write specifications

A B

$2$

E

Run prints

C D

$1$

F

Have specifications printed

B D

$3$

G

Assemble bid package

E F

$1$