What is the remainder when (55)(57) is divided by 7?
Choices:
A) 1  B) 2  C) 3  D) 5  E) 6

Rationale: "( 55 ) ( 57 ) = ( 56 - 1 ) ( 56 + 1 ) = 56 ^ 2 - 1 which is 1 less than a multiple of 7 . then the remainder will be 6 . the answer is e ."
Answer: E