Given a latex: n\times mn × m chocolate bar, you need to break it into nm 1 by 1 pieces. you can break a bar only in a straight line, and only one bar can be broken at a time. can you solve the problem with the minimum number of bar breaks? note: you can use plain english to describe your answer. 1). what is this minimum number? 2). justify your answer by using properties of a binary tree.