by adding magnesium to molten cast iron

by quick cooling of molten cast iron

from white cast iron by annealing process

none of these

white cast iron

nodular cast iron

malleable cast iron

alloy cast iron

hardness

ductility and strength in tension

corrosion resistance

creep strength

silicon

Sulphur

Manganese

Phosphorus

carbon in the form of free graphite

high tensile strength

low compressive strength

all of these