2. Perform the modular arithmetic for the following questions, use quick reductions as often as you can, don't use calculator. 1) 15 x 28 mod 13 2)-11 x 41 mod 15 3) 7100 mod 13 4)7 x 2/5 mod 7 (hint: you'll need to calculate 5 mod 7) 5) 61 mod 12 3. Find all integers n between 0