difficult / hard, probably impossible

The number 9 enclosed in a circle, used in enumerating lists.

(fandom slang) The Touhou character Cirno, known affectionately as an idiot.

question, problem on homework etc. / a question; a matter (of time etc.) / a problem (something that needs to be dealt with); a trouble / an issue; a matter

what number (in an order), whatth, how manyth

(informal) no problem

unthinkable, out of the question

practical question (problem)

matter of life or death / (idiomatic) an extremely urgent matter

viewing as a problem