A Company Is Designing a Product Layout for a New

A company is designing a product layout for a new product. It plans to use this production line eight hours a day in order to meet projected demand of 480 units per day. The tasks necessary to produce this product are: $$\begin{array} { l l l } \text { Task } & \text { Time (secs) } & \text { Immediate Predecessor } \\\hline \mathrm { u } & 30 & \text { none } \\\mathrm { v } & 30 & \mathrm { u } \\\mathrm { w } & 6 & \mathrm { u } \\\mathrm { x } & 12 & \mathrm { w } \\\mathrm { y } & 54 & \mathrm { x } \\\mathrm { z } & 30 & \mathrm { v } , \mathrm { y }\end{array}$$ If the company wants the output rate to be equal to demand, what would be the efficiency of this line with the minimum number of workstations?

A) 100 percent
B) 92.5 percent
C) 75 percent
D) 87.5 percent
E) 90 percent