TIME $($DAYS$)$ ACTIVITY a m b IMMEDIATE PREDECESSOR$($S$)$ A $368$ B $244$ C $123$ D $678$ C E $246$ B$,$ D F $61014$ A$,$ E G $124$ A$,$ E H $369$ F I $101112$ G J $141620$ C K $2810$ H$,$ I a$)$ Determine the expected completion time and variance for each activity. b$)$ Determine the total project completion time and the critical path for the project. c$)$ Determine ES$,$ EF$,$ LS$,$ LF$,$ and slack for each activity. d$)$ What is the probability that Kelle Carpet and Trim will finish the project in $40$ days or less?