The correct option(s) related to the extraction of iron from its ore in the blast furnace operating in the temperature range $900-1500 \mathrm{~K}$ is(are)

Considering the following reaction sequence, the correct statement(s) is(are)

Among the following, the correct statement(s) about polymers is(are)

Atom $\mathrm{X}$ occupies the fcc lattice sites as well as alternate tetrahedral voids of the same lattice. The packing efficiency (in %) of the resultant solid is closest to