The following is a table of activities associated with a project at Rafay Ishfaq's software firm in Chicago, their durations and what activities each must precede: This exercise contains only parts b,c, and d. b) The activities on the critical path are c) The total project completion time for Rafay Ishfaq's software firm is weeks. (Enter your response as a whole number.) d) Determine the slack time for each of the activities. (Enter your responses as whole numbers.)