Read this and answer the question. If the question is unanswerable, say "unanswerable".

Although critics have blamed Napoleon for several tactical mistakes preceding the battle, they have also praised his audacity for selecting a risky campaign strategy, choosing to invade the Italian peninsula from the north when the vast majority of French invasions came from the west, near or along the coastline. As Chandler points out, Napoleon spent almost a year getting the Austrians out of Italy in his first campaign; in 1800, it took him only a month to achieve the same goal. German strategist and field marshal Alfred von Schlieffen concluded that "Bonaparte did not annihilate his enemy but eliminated him and rendered him harmless" while "[attaining] the object of the campaign: the conquest of North Italy."

Around how long did it take Napoleon to push Austria out of Italy in his first experiences there?
a year