TOPIC: Activity Diagram explanation

Hi
Require help in understanding the below question. source oliver lehman 75 questions
You just created the following network logic diagram to describe the planned flow of activities for your project which will start tomorrow:

Which potential inconsistency in the diagram should you solve right now?


Activity E is a logical dangle in relation to the sink before the finish milestone.
Activity F is a logical dangle in relation to the burst point after the start milestone.
You cannot calculate a critical path when lags and/or leads are calculated in percent.
Activities E to F need another task drawn as a hammock to calculate Level Of Effort.