Motorcycle Repair: motorcycle disc brake size, disc brake rotors, pitch diameter

Question
i want to import a petal shape motorcycle disc brake rotors from a supplier,for which the supplier has asked me for various size specifications.viz.
A   :    Disc diameter                E  :    Swept height  
B  :    Center hole diameter  F  :    Offset  
C  :    Bolt pitch diameter  No  :    Number of bolts  
D  :    Bolt hole size  Disc thickness = 5 mm


i have difficulty calculating "C"  bolt pitch diameter.please help  

Answer
I believe they are referring to what is also referred to as "bolt circle diameter", which is the diameter as measured through the center of each bolt hole around the disc. In other words, if you have five bolt holes in the disc, then their "bolt circle" is the diameter of the circle passing through the center of all the holes.