The same screen that lists possible modes presents additional information about the task.
To perform a task in any given mode resources may be required.
In the example above, task C requires one unit of a resource called worker during its execution.
The actual cost of the worker performing task C depends on the task's actual duration that may be deterministic or randomly generated by PTB" The fixed cost of the task represents the cost that is independent of the task's actual duration. For example, a fixed cost is the cost of material required to perform the task. The number of resource units required of each resource type is defined by the mode the assumption is that the task cannot be executed unless all the required resources are available in the required quantities.