Identify the correct set of $13^{th}$ group elements which do not form amphoteric oxides?

Which of the following has the highest ratio of reducing hydrogen atoms to $OH$ groups?

What is the product of the reaction between $HNO_3$ and $P_4O_{10}$?

$Fe$ is made passive by

$A$ $p$-block element $(E)$ and hydrogen form a binary cation $(EH_{x}^{+})$, while $EH_{3}$ on treatment with $K_{2}HgI_{4}$ in alkaline medium gives a precipitate of basic mercury$(II)$amido-iodine. Given below are first ionisation enthalpy values $(kJ \ mol^{-1})$ for the first element of each group $13, 14, 15$, and $16$. Identify the correct first ionisation enthalpy value for element $E$.

Which one of the following compounds on strong heating evolves ammonia gas?