Construction of the Cattery Could Be Distilled to Eight Distinct

Construction of the cattery could be distilled to eight distinct steps, from the official groundbreaking ceremony to the cutting of the litterbox ribbon. The activities, their durations and predecessors are shown in the table below. Determine earliest and latest start and finish times for all of the activities.
$$\begin{array} { | c | c | c | } \hline \text { Activity } & \text { Predecessors } & \text { Time (weeks) } \\\hline \text { A } & \cdots & 10 \\\hline \text { B } & \text { A } & 8 \\\hline \text { C } & \text { A } & 7 \\\hline \text { D } & \text { C } & 11 \\\hline \text { E } & \text { D } & 12 \\\hline \text { F } & \text { B } & 11 \\\hline \text { G } & \text { E, F } & 6 \\\hline \text { H } & \text { E, F } & 9 \\\hline\end{array}$$