Select (i) combination reaction, (ii) decomposition reaction and (iii) displacement reaction from the following chemical equations : (i) $\mathrm{ZnCO}_3$ (s) $\rightarrow \mathrm{ZnO}(\mathrm{s}) + \mathrm{CO}_2$ (g)(ii) $\mathrm{Pb}$ (s) $+ \mathrm{CuCl}_2$ (aq) $\rightarrow \mathrm{PbCl}_2$ (aq) $+ \mathrm{Cu}$ (s)(iii) $\mathrm{NaBr}(\mathrm{aq}) + \mathrm{AgNO}_3$ (aq) $\rightarrow \mathrm{AgBr}($ s)$+ \mathrm{NaNO}_3(\mathrm{aq})$(iv) $\mathrm{H}_2$ (g) $+ \mathrm{Cl}_2$ (g) $\rightarrow 2 \mathrm{HCl}$ (g)(v) $\mathrm{Fe}_2\mathrm{O}_3 + 2 \mathrm{Al} \rightarrow \mathrm{Al}_2\mathrm{O}_3 + 2 \mathrm{Fe}$(vi) $3 \mathrm{H}_2(\mathrm{g}) + \mathrm{N}_2(\mathrm{g}) \rightarrow 2 \mathrm{NH}_3(\mathrm{g})$(vii) $\mathrm{CaCO}_3$ (s) $\xrightarrow[]{\text{ Heat }} \mathrm{CaO}$ (s) $+ \mathrm{CO}_2$ (g)