The atomic numbers of the metallic and non-metallic elements which are liquid at room temperature respectively are

Which of the following pairs of atomic numbers represents elements of the same group?

In the periodic table,metallic character of the elements shows which one of the following trends?

Fluorine is a stronger oxidising agent than chlorine in aqueous solution. This is attributed to many factors except

Given below are two statements:
Statement $I$: The number of pairs among $[Al_2O_3, Cr_2O_3]$,$[Cl_2O_7, Mn_2O_7]$,$[Na_2O, V_2O_3]$ and $[CO, N_2O]$ that contain oxides of same nature (acidic,basic,neutral or amphoteric) is $4$.
Statement $II$: Among $Na_2O, Al_2O_3, CO$ and $Cl_2O_7$,the most basic and acidic oxides are $Na_2O$ and $Cl_2O_7$,respectively.

Which of the following oxides is the most basic oxide?