An element X forms two oxides XO and XO₂. The oxide XO is neutral but XO₂ is acidic in nature. The element X is most likely to be :

75 Out of the following oxides, the amphoteric oxide is: 76 The metals which can produce amphoteric oxides are: 78 The elements whose oxides can turn litmus solution blue are: 79 The elements whose oxides can turn litmus solution red are :