What is the oxidation state of gallium?

Which of the oxidation state$(s)$ is/are shown by the element sulphur?

Which of the following elements exhibits variable oxidation states?

Consider the following information about elements $P$ and $Q$:

Element	Period and Group
$Q$	Period $2$,Group $15$
$P$	Period $3$,Group $2$

Then the formula of the compound formed by $P$ and $Q$ elements is:

Two elements $X$ and $Y$ have the following electronic configurations: $X = 1s^2, 2s^2 2p^6, 3s^2 3p^6, 4s^2$ and $Y = 1s^2, 2s^2 2p^6, 3s^2 3p^5$. The expected compound formed by the combination of $X$ and $Y$ is:

Which is the correct oxidation state of lead?