Which of the following is true regarding estimates of completion of units in a process costing system? Select one: estimating the degree of completion with regards to conversion costs is more of a science than an art b. estimating the degree of completion with regards to conversion costs is usually easier and more accurate than estimating the degree o a direct materials o c estimating the degree of completion with regards to direct materia's is usually easier and more accurate than estimating the degree of completion with regards to conversion costs d. when estimating degree of completion, the degree of completion with regards to conversion costs is usually a portion similar to the degree of completion with regards to direct materials