A 'cup' turns out to have a precise meaning as a measurement for Americans. A 'cup (US) ' is 24 centilitres, near enough, according to an American website. Now isn't that useful ? All right, maybe not ! (Believe it or not , the same site claims there's 'a cup (metric)' , but enough is enough !).
Hope you are going to personally check the product for taste (as the late Barbara Woodhouse used to). Can't be too careful ! LOL Commercial dog biscuits taste very bland, I think, but then I've not got a dog's sense of smell and taste. One of mine goes hunting through a selection of the mixed shaped ones, picking out the cream, bone-shaped, ones first !