Gating ratio of $$1:2:4$$ is used to design the gating system for magnesium alloy casting. This gating ratio refers to the cross section areas of the various gating elements as given below

$$1.$$ $$Down$$ $$sprue$$ $$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$2.$$ $$runner$$ $$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$3.$$ $$Ingates$$
The sequence of the above elements in the ratio $$1:2:4$$ is

Chapters are placed between mould and core surfaces in order to :

Which one of the following is NOT a property of a sand mold?

In resistance welding, heat is generated due to the resistance between