* Activity Details (9001 - "Spillway - Concrete"):
* Duration: 175 days in the Normal schedule.
* To calculate Late Start (LS), the Late Finish (LF) is required. LS is calculated by subtracting the activity's duration from the LF.
* Formula for Late Start (LS):LS = LF.9001 - Dur.9001.
* Date Calculation:
* Late Finish (LF.9001) = 11-20-02 (given or derived).
* Apply the formula:LS.9001 = LF.9001 - Dur.9001= 11-20-02 - 175 days.
* Cross-Verification of Dates:
* After subtracting 175 days, LS.9001 = 11-20-02.
* Cross-Verification with Answer Options:
* Option A: Incorrect. EF (Early Finish) is not needed for this calculation.
* Option B: Incorrect. Uses LS and Dur incorrectly without connecting to LF.
* Option C: Incorrect. Data provided is sufficient.
* Option D: Correct. Matches both the formula and the date calculation.
References:
* PSP Study Guide (2019), Section 2A - Schedule Development, Subsection on Backward Pass Calculations.
* AACE Recommended Practices, RP 10S-90, discussing Late Start and Late Finish calculations.