What is the percentage $(\%)$ of silver in German silver?

What is the percentage of carbon in steel?

The correct statement$(s)$ related to the metal extraction processes is(are):
$(A)$ $A$ mixture of $PbS$ and $PbO$ undergoes self-reduction to produce $Pb$ and $SO_2$.
$(B)$ In the extraction process of copper from copper pyrites,silica is added to produce copper silicate.
$(C)$ Partial oxidation of sulphide ore of copper by roasting,followed by self-reduction produces blister copper.
$(D)$ In the cyanide process,zinc powder is utilized to precipitate gold from $Na[Au(CN)_2]$.

Among statements $(a)-(d),$ the correct ones are
$(a)$ Limestone is decomposed to $CaO$ during the extraction of iron from its oxides.
$(b)$ In the extraction of silver,silver is extracted as an anionic complex.
$(c)$ Nickel is purified by Mond's process.
$(d)$ $Zr$ and $Ti$ are purified by Van Arkel method.

Match List-$I$ with List-$II$ (Both having metallurgical terms):

List-$I$	List-$II$
$A$. Concentration of $Ag$ ore	$I$. Reverberatory furnace
$B$. Blast furnace	$II$. Pig iron
$C$. Blister copper	$III$. Leaching with dilute $NaCN$ solution
$D$. Froth floatation method	$IV$. Sulfide ores

Choose the correct answer from the options given below:

$A$ metal $(M)$ exists in oxide form. Its oxide cannot be reduced by carbon up to $800\, ^\circ C$,but it can be reduced by $Al$ even below $800\, ^\circ C$. Select the correct Ellingham diagram for metal $(M)$.