Final answer:
LS and LF are calculated using both the backward and forward pass through the network in project scheduling to identify critical paths and potential bottlenecks.
Step-by-step explanation:
The LS (Late Start) and LF (Late Finish) are calculated using the d. backward and forward pass through the network. The forward pass is used to determine the earliest possible start and finish times for activities (ES and EF), while the backward pass is used to calculate the latest possible start and finish times without delaying the project (LS and LF). It is important to understand both passes in the context of project scheduling and management, as they help in identifying the critical path and any potential bottlenecks.