Answer 1

Roasting	Calcination
Ore is heated in excess of air.	Ore is heated in the absence or limited supply of air.
This is used for sulphide ores.	This is used for carbonate ores.
SO2 is produced along with metal oxide.	CO2 is produced along with metal oxide.
e.g. \[\ce{ 2ZnS + 3O2 ->[\Delta] 2ZnO + 2SO2}\]	e.g. \[\ce{ZnCO3 ->[\Delta] ZnO + CO2}\]