Activity	Preceding Activity	Optimistic Time	Probable Time	Pessimistic Time
A	-	2	3	4
B	A	3	5	7
C	B	1	2	3
D	C	2	3	10
E	B	5	6	7
F	D	4	8	12
G	B	1	2	3
H	G	3	4	11
I	E,G	4	5	6
J	F,H,I	3	3	3
K	J	3	5	10

a). Tabulate the ES, EF, LS, LF and the slack of each activity. (4 marks)

b). Demonstrate the project activities and their respective expected times in a Gantts Chart. (8 marks)

Pls explain more details how to get it the ES, EF, LS, LF and the slack of each activity. ? Because I Dont know how to get pls help!