Which of the following holds Choose all that apply if a = b mod(m), then b = a mod(m) if a = b mod(m), and a = c mod(m), then b = c 16^n mod (7) = 2^n mod (7), where ^ is the exponent and n is a number with 200 digits if b = a mod(m), and c = b mod(m), then b = c mod(m), then b + c = o mod (m)