Metallurgy is the process of

Among statements $(a)-(d),$ the correct ones are
$(a)$ Limestone is decomposed to $CaO$ during the extraction of iron from its oxides.
$(b)$ In the extraction of silver,silver is extracted as an anionic complex.
$(c)$ Nickel is purified by Mond's process.
$(d)$ $Zr$ and $Ti$ are purified by Van Arkel method.

Which of the following metals is present in Brass,Bronze,and German silver?

Extraction of copper from copper pyrite $CuFeS_2$ involves:
$A$. Crushing followed by concentration of the ore by froth-flotation
$B$. Removal of iron as slag
$C$. Self-reduction step to produce 'blister copper' following evolution of $SO_2$
$D$. Refining of 'blister copper' by carbon reduction

Bronze is a mixture of . . . . . . metals.

Match List-$I$ (substances) with List-$II$ (processes) employed in the manufacture of the substances and select the correct option.

List-$I$ (Substances)	List-$II$ (Processes)
$A$. Sulphuric acid	$i$. Haber's process
$B$. Steel	$ii$. Bessemer's process
$C$. Sodium hydroxide	$iii$. Leblanc process
$D$. Ammonia	$iv$. Contact process