How Do Forces Distribute in a Block and Tackle System?

[ksle82]

Given a block and tackle system and a known weigt, give the magnitude of the forces at the numbered points. [see attached for figure]
https://www.physicsforums.com/attachment.php?attachmentid=7026&stc=1&d=1149034106
blocktackle.JPG

My answers:
Point 2: 20
Point 3: 20
Point 4: 10
Point 1: 40

I arrived at the answers simply by looking at the figure and do a force balance at each tackle. I think some (if not all) are wrong because the systems doesn't provide any mechanical advantage (according to my answers). Please Help.

 

[Doc Al]

Looks OK to me (assuming all ropes are essentially vertical). Why do you say there's no mechanical advantage? A 10 unit weight (shown) lifts a 20 unit weight (that's point 2).