At the End of Each Month, a Research and Development

At the end of each month, a research and development team writes status reports for the projects worked on during the month. The team leaders, Andrew and Julie, submit the reports to the R&D director on the first Monday of each month. It is late Friday evening and to their surprise, they discover that the month ends on Sunday, and the reports are due on Monday morning. They decide to come to work early Saturday morning, so they can finish the reports before Monday morning. They split the work as follows: Andrew will write and edit the reports, while Julie collates data and draws all the necessary graphs. Assume that Julie starts her work on a report as soon as Andrew is finished with it and that Andrew works continuously. Times for the reports (in hours) are as follows:
$\begin{array}{|c|c|c|}\hline \text { Projects } & \text { Andrew } & \text { Julie } \\\hline \text { A } & 4 & 2 \\\hline \text { B } & 3 & 5 \\\hline \text { C } & 5 & 1 \\\hline \text { D } & 7 & 3 \\\hline \text { E } & 8 & 6 \\\hline\end{array}$
a.What is the order of the projects using Johnson's rule?
b.How many hours will it take them to finish all the reports?
c.How many hours is Andrew idle?
d.How many hours is Julie idle?