Which of the following metals is present in Brass,Bronze,and German silver?

Flux is used to remove ...... .

The $INCORRECT$ statement is:

Match items of Column-$I$ with the items of Column-$II$ and assign the correct code :

Column $I$	Column $II$
$A$. Cyanide process	$i$. Ultrapure $Ge$
$B$. Froth floatation	$ii$. Dressing of $ZnS$
$C$. Electrolytic reduction	$iii$. Extraction of $Al$
$D$. Zone refining	$iv$. Extraction of $Au$
	$v$. Purification of $Ni$

Given below are two statements:
Statement $I$: During electrolytic refining,the pure metal is made to act as anode and its impure metallic form is used as cathode.
Statement $II$: During the Hall-Heroult electrolysis process,purified $Al_2O_3$ is mixed with $Na_3AlF_6$ to lower the melting point of the mixture.
In the light of the above statements,choose the most appropriate answer from the options given below:

For the following statements,mark $T$ for true and $F$ for false statement.
Statement $1$: $SnO_2 +$ wolframite,in this $SnO_2$ is magnetic while wolframite is non-magnetic in nature.
Statement $2$: Argentite ore is concentrated by froth floatation method.
Statement $3$: Copper and lead ores are reduced by self-reduction method.
Statement $4$: In metallurgy of $Fe$,$CO$ is used as a reducing agent at low temperature.