Which one of the following methods can be used to obtain highly pure metal which is liquid at room temperature?

Blister copper is refined by stirring molten impure metal with green logs of wood because such wood liberates hydrocarbon gases (like $CH_4$). This process $X$ is called . . . . . . . . . and the metal contains impurities of $Y$ is . . . . . . . . .

Refining of tin cannot be done by

The process of zone refining is used in the purification of

If a metal has low oxygen affinity,then the purification of the metal may be carried out by:

The formation of $Ni(CO)_4$ and its subsequent decomposition into $Ni$ and $CO$ forms the basis of the Mond process.
$Ni + 4CO$ $\xrightarrow{T_1} Ni(CO)_4$ $\xrightarrow{T_2} Ni + 4CO$
What are the values of $T_1$ and $T_2$?