"Excuse me, is that building a museum?"
Translation:Anteeksi, onko tuo rakennus museo?
Usually one incorrect letter per word is accepted as a typo, while more than one incorrect letter is an error and the answer is not accepted. I've sometimes stumbled on this because I have had the correct letters but two of them have switched places and hence it's been considered two incorrect letters by the algorithm. Since "rakkenus" has an extra 'k' and is missing an 'n' the algorithm detects two errors, even though a Finn would easily know which word you meant.
I don't believe so.
In a sentence with this construction, subject-on-predicative noun, the predicative noun would be partitive if it were an uncountable noun. Thus 'Kala on lihaa', since 'meat' is an uncountable mass noun.
But the predicative is nominative when it's a singular countable noun. Museo is a countable noun, and is therefore nominative.