(10 points) Prove uniqueness. That is, if r1 and r2 are both remainders after the division of b by a, then r1 = r2. You can use without proof reasonable facts about integer multiplication, addition, subtraction, and >, but don’t assume anything about integer division. In particular, you can use the fact that there are no integer multiples of a that are greater than 0 and less than a. Hint: Use proof by contradiction combined with proof b