please solve it without Excel

sum student ID =20

2. Project activities on installing high-tech manufacturing lines on a newly founded factory are demonstrated below. Because of the privacy restrictions of the company, the activities are denoted with some of the letters in the alphabet. The project is expected to start at the 18th day of the next month. According to these, answer the following questions: Activities Immediate Time (day) predecessors A 4 B 3 A 3 D A 5 E B 9 F B 4 G DE 9 H E 7 I C,G 5 J 1,H.F 8 K J 6 a) Draw the project network and identify the critical path indicating time duration for each path. b) What is the expected project length? c) Calculate ES, EF, LS, LF and slack times for each activity and indicate the values on the network. d) Draw up a Gantt chart