Can someone Explain This..Oliver Lehmann

11. In the following network logic diagram start dates are defined as early morning, finish dates are evening.
If tasks are scheduled to begin at early start date, what is true?

A. Activity B has a free float of 10 d.
B. Activity B has a total float of 10 d.
C. Activity A has a free float of 10 d.
D. Activity A has a total float of 10 d.
Answer is B

Also, i scored 66 % in Oliver Lehmann..How am i doing? Any suggestions.. Is it a difficult or relatively easy sample exam paper?

 This question is incomplete. Where is the diagram refered to?

I did paste it...but for some reason it is deleted.

 can u post that on www.pmptrend.com forum and i will decipher that question for u

Not able to paste it...sorry

 This feature is absent here in pmzilla thats why whenever i make detailed explanation with charts, i post it on www.pmptrend.com forum.

Oliver F. Lehmann's picture

 The question has meanwhile moved to become #18 at  http://www.oliverlehmann.com/pmp-self-test/75-free-questions.htm.

Free float is the time that an activity can be delayed without impacting another activity. Activity B can be delayed by 9 days without impacting Activity D, which is intended to start on the morning of the tenth day after (early) finish of Act. B.

Total float is the time difference between early start and late start or early finish and late finish dates. In the example, this is 10 days for Act. B.

Act. A has a free float of 0 and a total float of one day.

Once you understand the concept, it is actually rather simple and straight forward.

Recommendation: Don't try to sit for the exam without a sound understanding of network diagramming. Some people consider it a core competency for a project manager, and these people may be among those who write questions for the test.