Astaamaha:
Safka koowaad ee ilig gaaban ayaa loo adeegsadaa farsamaynta bilowga ah, safka labaad ee ilkuhuna si fiican ayaa loo farsameeyey si loo dhamaystiro dunta.Naqshadeynta bidix ee qalabka wax lagu gooyo waxay u baahan tahay lafdhabarta si ay u beddesho goynta bidix si loo yareeyo xoogga goynta oo loo kordhiyo xoogga goynta qalabka.Ku habboon farsamaynta walxaha ad-adag sare leh sida birta caaryada birta la demiyay ee ka sarreysa 48HRC.