The following four activities were identified as being on the critical path of a large project. The project manager wished to reduce the completion time by one week. Which activit should be crashed first? Activity Normal Time Normal Crash Crash Time (weeks). Cost Cost (weeks) 12 $15,000 8 $18,000 8 $17,500 $18,850 9 $12,200 $14,750 11 $12,780 7 $14,500 OA O OC OD O cannot tell from the information given