Critical Path Method

Correct Answer: The project end date is extended by 2 days.

Given the conditions of this project as per the question, Task A must be completed before both Tasks B and C can begin. Then, Task D cannot start until Task B is completed, and Task E can start as soon as Task C is completed. If Task B, which must be completed before Task D can begin, takes 2 days longer than expected, this means that the start of Task D will have to be delayed by the same amount of time. This delay will have a direct impact on the project's end date since it's dependent on the completion of all tasks. Therefore, the end date of the project will be extended by 2 days The other answers are incorrect for the following reasons: 'The project end date remains unchanged.' - This is not accurate as the delay in task B directly affects task D and hence, will extend the project's end date 'The project end date is shortened by 2 days.' - This is logically incorrect because a delay in a task of the project cannot result in shortening the project's end date 'The project end date is extended by 1 day.' - This is also not a correct assumption. Any delay in Task B that is crucial for the start of Task D, will affect the project end date with the same amount of delay, in this case, 2 days.

Correct Answer: 15 days

The correct answer is 15 days. In project network diagrams, the Early Finish (EF) of a task is calculated by adding the Early Start (ES) and the task duration. Early Finish (EF) = Early Start (ES) + Task Duration Given: Early Start (ES) = 10 days Task Duration = 5 days Early Finish (EF) = 10 days + 5 days = 15 days This calculation provides the earliest possible completion time for the task, assuming no delays or interruptions. The other options are incorrect: 20 days is an overestimation and does not follow the correct calculation method. 10 days incorrectly assumes that the Early Start determines the Early Finish, which is not the case. 5 days only considers the task duration and does not account for the Early Start time.

Correct Answer: They have zero total float.

In the Critical Path Method, activities on the critical path have zero total float. This means there is no flexibility in their scheduling; any delay in these activities will directly delay the project's completion date. Therefore, the total float of activities on the critical path is zero. The other options are incorrect because activities on the critical path do not have maximum possible float, nor do they possess unlimited total float. Their float does not equal the project duration.