The activity table is given below

Activity

Predecessor

Duration

ES

LE

0-1

Clear site

3

1-2

Survey and layout

2

2-3

Rough grade

2

7

3-4

Drill wel

15

22

3-6

Water tank foundations

4

12

3-9

Excavate sewer

10

21

3-10

Excavate electrical manholes

1

21

3-12

Pole line

6

29

4-5

2

22

Well pump.

24

a) Draw the CPM network with path duration and determine the critical path

b) Draw the CPM path with ES, EF,LS,LF and determine the critical path