Which of the following oxides is amphoteric?

In the following reaction,identify the nature of the product formed by the complete hydrolysis of the underlined atom at $R.T.$:
$\underline{S}O_3 + H_2O \longrightarrow H_2SO_4$

$(1)$ Half-life of $^{14}C$ is $...........$
$(2)$ $..........$ isotope of carbon is used in radiocarbon dating.
$(3)$ Main component of ceramic,cement and glass is $........$

Which of the following oxides reacts with both $HCl$ and $NaOH$?

The correct order of catenation is

Which of the following statements are correct?
$1.$ Charcoal can be obtained by heating wood in the absence of air.
$2.$ Charcoal is an impure form of graphite.
$3.$ Diamond is thermodynamically the most stable allotrope of carbon.
$4.$ Coke is used as an oxidising agent during the extraction of iron from its ores.