- Blue broke rule 10 regarding Green but she shall be exonerated by rule 21 (and 64.1(a)) because she is the boat entitled to room (by rule 16.1) by Green which did not give her this room.Blue did not broke any rules regarding Yellow.
- Green broke rule 16.1 regarding Blue but she shall be exonerated by rule 21 (and 64.1(a) ) because Yellow broke rule 16.1
- Yellow broke rule 16.1 regarding Green but she shall be exonerated by rule 21 because she is the boat entitled to markroom (by rule 18.2) by Green (only!)
Here the key question is - did Yellow breaking rule 16.1 regarding Blue or not?
I think – yes, she did (see the Definition Room: «including space to comply with her obligations under the rules of Part 2» ).
And Yellow can not be exonerated by rule 21 for it because she is not entitled to room or mark-room regarding Blue.