Normal spoilage is 6% of good units passing inspection in a forging process. In March, a total of 13,000 units were spoiled. Other data include units started during March, 190,000; work in process, beginning, 17,000 units (20% completed for conversion costs); and work in process, ending, 14,000 units ( 70% completed for conversion costs). Compute the normal and abnormal spoilage in units, assuming the inspection point is at (a) the 15% stage of completion, (b) the 40% stage of completion, and (c) the 100% stage of completion.