During the construction of a house there are certain tasks that have to be completed before another one can commence, e.g., the roof has to be installed before the work on electrical wiring or plumbing can begin. How can a graph be used to model the different tasks during the construction? Should the edges be directed or undirected? By analyzing the graph model, how can we find tasks that can be done at any time? Knowing the amount of time that each task takes, what do we need to compute to find the minimum length of time necessary to build the whole house (assuming enough resources are always available)?