Six jobs will be processed in a two-step operation. The first operation involves sanding and the second painting. Processing times are as follows:

a) Determine the sequence that minimizes the total time required to complete these jobs. b) Determine the total operating time and idle time if any. c) Make the graphic illustration.

\begin{tabular}{|c|c|c|} \hline TRABAJO & LIJAR (Horas) & Pintar (Horas) \\ \hline I & 4 & 5 \\ \hline II & 16 & 14 \\ \hline III & 8 & 7 \\ \hline IV & 12 & 11 \\ \hline V & 3 & 9 \\ \hline \end{tabular}