The Learner Company uses the weighted average method. Learner's beginning work in process consists of 6,600 units (100% complete with respect to materials and 60% complete with respect to conversion costs). The number of units completed is 126,000. The ending work in process consists of 10,500 units (100% complete with respect to materials and 30% complete with respect to conversion costs). Calculate the number of units started during the period. a. 100,000 b.120,000 c.129,900 d.133,500