You Have Collected the Data for a Time-Cost CPM Scheduling

You have collected the data for a Time-Cost CPM Scheduling model analysis.The time is in days and the project "direct costs" are given below. $$\begin{array} { | l | l | l | l | l | l | } \hline & \text { Immediate } & \text { Normal } & \text { Crash } & \text { Normal } & \text { Crash } \\\hline \text { Activity } & \text { Immediate } & \text { Time } & \text { Time } & \text { Cost (Direct) } & \text { Cost (Direct) } \\\hline \text { A } & \text { None } & 3 & 2 & \$ 300 & \$ 400 \\\hline \text { B } & \text { A } & 3 & 3 & \$ 100 & \$ 100 \\\hline \text { C } & \text { A } & 1 & 1 & \$ 200 & \$ 200 \\\hline \text { D } & \text { B and C } & 3 & 2 & \$ 400 & \$ 550 \\\hline \text { E } & \text { D } & 2 & 1 & \$ 500 & \$ 900 \\\hline \text { F } & \text { E } & 3 & 3 & \$ 200 & \$ 200 \\\hline \text { G } & \text { F } & 2 & 2 & \$ 100 & \$ 100 \\\hline\end{array}$$
The indirect costs for the project are determined on a daily duration basis.If the project lasts 16 days the total indirect costs are $400,15 days they will be $250,14 days they will be $200,and 13 days they will be $100.At what day do we achieve the lowest total project cost (i.e. ,direct plus indirect costs) ?

A) 16 days
B) 15 days
C) 14 days
D) 13 days
E) 12 days