What are oxo-acids?

Which of the following statements are incorrect about the oxidation state and acidic nature of oxo-acids?

Which of the following reaction(s) do/does not givean oxo-acid?

Write two properties of alkali metals salts of oxo-acids.

Write two properties of alkali metals salts of oxo-acids.

Which of the following reaction(s) do/does not give an oxo-acid?

Write two properties of alkali metals salts of oxo-acids.

What are acidic amino acids?