Table 920
the Following Information Is Known About an Assembly Line

Table 9.20
The following information is known about an assembly line.
The desired output rate is 80 units per hour.
$$\begin{array} { | c | c | c | } \hline \begin{array} { c } \text { Work } \\\text { Element }\end{array} & \text { Time (sec) } & \begin{array} { c } \text { Immediate } \\\text { Predecessor } ( \mathrm { s } ) \end{array} \\\hline 1 & 1 & - - \\2 & 15 & 1 \\3 & 20 & 1 \\4 & 30 & 2 \\5 & 20 & 2,3 \\6 & 10 & 5 \\7 & 20 & 4 \\8 & 4 & 6,7 \\\hline\end{array}$$
-Use the information in Table 9.20.Using the longest work-element time rule of line balancing,what is the theoretical minimum number of stations versus the number of stations needed?

A) 2 versus 3
B) 3 versus 3
C) 3 versus 4
D) 4 versus 2