SolidWorks mold making problems and solutions

Good morning,

my target is: to pass mold making exam; I have exercises to do for my preparation but I have many doubts;

can you help me? I write my questions:

1)

I have a part; I have created the division line and the closing surface; next step is "create conical interlocks around the perimeter of the parting surface; type: conical to vector/8 degrees (top plane)/ for 15 mm;

What does it mean "create conical interlocks around the perimeter of the parting surface?

I think to use Ruled surface but I'm not sure.

I have the files and the originale text, but I don't know if is possibile to post it or not (because they are exam CSWP original files).

(Sorry for my english... is not very good :-( )

Thanks to all, technical colleagues :-)

SolidworksPlastics And Mold Design