The least reactive metal among the following is:

71 You are given a solution of AgN03. Which of the following do you think cannot displace Ag from AgN03 solution? 72 Out of aluminium, copper, calcium and tin, the most reactive metal is: 74 An element X reacts with hydrogen, when heated, to form a covalent hydride H₂X. If H₂X has a smell of rotten eggs, the element X is likely to be: 75 Out of the following oxides, the amphoteric oxide is: