"appropriate" or "right"?

[simplythebest]

Hi,

Could you tell me if "appropriate" is correct in:
Circle the hidden answers to the questions. Then write them in the appropriate boxes, using the necessary punctuation marks.

Should I use "right" instead of "appropriate" ?
Can "hidden" be used as an adjective before a noun as in the sentence above (the answers are hidden in a word search puzzle)

Thank you very much,
simplythebest