If the freezing ratio equal to (casting area/casting volume)/(riser area/riser volume) & the volumetric ratio equal to riser volume/casting volume, for a disc casting of $$20cm$$ diameter and $$10$$ $$cm$$ thick are $$1.4$$ and $$0.8$$ respectively. The corresponding values for a square disc of $$20$$ $$cm$$ side and $$10$$ $$cm$$ thick if the same cylindrical riser with a height to diameter ratio of unity is used in both cases.

Chaplets are placed between mold in order to

Investment casting uses ......... (wax / resin coated sand) as pattern material and is preferred for small parts with ................. (simple/intricate) designs

Investment casting uses ...... A........... as pattern material and is preferred for small parts with .......... B.........designs.

A. wax / resin coated sand
B. simple / intricate