May I get an answer to letters B , C, D please

b) c) d) Identify the variance for each activity and of each path Identify the critical path Compute for z value, the Pz (Normal standard distribution) and plot in a graph ACTIVITY IMMEDIATE PREDECESSORS to tm tp B C D E F G H 1 J K L M AB A.C B.C DE D,F EF GH G, HI JK KL TIME ESTIMATES (days) 2 3 6 12 15 6 7 9 4 12 5 1 2 1 3 2 5 3 1 1 4 2 1 2 4 4 3 8 4 7 6 3 5 6 6 4 4 6 8 8 10 6 9 8 6 9 10 7 6 7 4 3