Use This Scenario for the Following Question(s) -Refer to the Scenario Above

Use this scenario for the following question(s) .
The process design team at a manufacturer has broken an assembly process into eight basic steps, each with a required time, and predecessor as shown in the table. There are 8 productive hours available in a day and the manufacturer wishes to produce 400 units. Use this information to answer the following question(s) .
$$\begin{array} { | c | c | c | } \hline \text { Task } & \text { Time } ( \mathrm { sec } ) & \text { Predecessor } \\\hline \mathrm { J } & 45 & \cdots \\\hline \text { K } & 50 & \mathrm {~J} \\\hline \mathrm { L } & 40 & \mathrm {~J} \\\hline \mathrm { M } & 55 & \mathrm {~K} , \mathrm {~L} \\\hline \mathrm { N } & 40 & \mathrm { M } \\\hline \mathrm { O } & 65 & \mathrm { M } \\\hline \text { P } & 25 & \mathrm {~N} \\\hline \text { R } & 35 & \mathrm { O } , \mathrm { P } \\\hline\end{array}$$
-Refer to the scenario above. Operations managers and process engineers design a line that contains seven stations. What is the percentage of idle time?

A) 21.9%
B) 14.3%
C) 25.6%
D) 17.8%