Which of the following is the strongest acid?

Regarding $F^{-}$ and $Cl^{-}$,which of the following statements is/are correct?
$(i)$ $Cl^{-}$ can give up an electron more easily than $F^{-}$
$(ii)$ $Cl^{-}$ is a better reducing agent than $F^{-}$
$(iii)$ $Cl^{-}$ is smaller in size than $F^{-}$
$(iv)$ $F^{-}$ can be oxidized more readily than $Cl^{-}$

The correct decreasing order for metallic character is:

Identify the correct order of acidic strengths of $CO_2, CuO, CaO, H_2O:-$

Among $Al_2O_3$,$SiO_2$,$P_2O_3$,and $SO_2$,the correct order of acidic strength is:

Use the periodic table to answer the following questions.
$(a)$ Identify an element with five electrons in the outer subshell.
$(b)$ Identify an element that would tend to lose two electrons.
$(c)$ Identify an element that would tend to gain two electrons.
$(d)$ Identify the group having metal,non-metal,liquid as well as gas at room temperature.