a 13.21 For a certain repetitive task, the snapback timing method was used to obtain the average work element times and performance ratings listed in the table below. Elements a, b, and care worker-controlled. Element dis a machine-controlled element and its time is the same each cycle (N.A. means performance rating is not applicable). Element cis performed while the machine is performing its cycle (element d). Element e is a worker-controlled irregu- lar element performed every six cycles. The machine is idle during elements a, b, and e. One part is produced each cycle. The machine allowance is 15%, and a 15% PFD allowance is applied to the manual portion of the cycle. Determine (a) the normal time and (b) the stan. dard time for this cycle. If the worker's performance during actual production is 130% on all manual elements for 7.3 actual hours worked on an 8-hour shift, (c) how many units will be produced and (d) what is the worker's efficiency? a Work Element Observed time (min) Performance rating (%) b 0.58 80 0.47 d 0.75 NA 0.70 110 2.10 85 90