Is there any reason why Duolingo doesn't actually TEACH the concepts? It's just not pedagogically sound to quiz me on a concept I've never been taught. I do not know the difference between zinatosha and kinatosha.
that isn't quite grammatically sound, it would translate to 'the food is to be enough', since 'kutosha' is the stem word of 'be enough/suffice/fit'. You could say 'chakula ni cha kutosha', because '-a kutosha' also means 'enough/sufficient'