You should know that any integer n can be expressed as 5k r, where k is an integer (called the quotient) and where the remainder r falls into five possible cases, r 0,1,2,3,4. the caser- is described as " is divisible by 5 prove that for any integer n, 5 divides n -n. (hint: you may want to review tho formula for (a y)5)