By annealing,steel

Match List-$I$ (Substances) with List-$II$ (Processes) used for their production.

List-$I$ (Substances)	List-$II$ (Processes)
$(a)$ Sulphuric acid	$(i)$ Haber process
$(b)$ Steel	$(ii)$ Bessemer process
$(c)$ Sodium hydroxide	$(iii)$ Leblanc process
$(d)$ Ammonia	$(iv)$ Contact process

Choose the correct option for $a-b-c-d$.

Identify the products of the reaction: $4FeCr_2O_4 + 8Na_2CO_3 + 7O_2 \rightarrow ?$

Which of the following statements is correct?

Stainless steel is an alloy of iron with:

Consider the following statements:
$(i)$ Froth flotation technique is used to concentrate sulphide ore.
$(ii)$ Froth flotation technique is based upon differential wettability of ore and impurity in water.
$(iii)$ Red Bauxite is concentrated by Bayer's process.
$(iv)$ Carbon is used as a reducing agent during the extraction of zinc from zinc blende.
Which of the following statements are correct?