Let R be a congruence relation modulo 7 on Z. Then the equivalence class [110] equals to which of the following: [2] [3] [1] [4] [5] If a = b (mod 5), then... Choose all correct statements. A. a+b = 0 (mod 10) B. ab = b2 (mod 5) C. 2(a - b) = ( (mod 20) D. a} = b3 (mod 5) E. a+ 7 = b + 12 (mod 5)