Each of six flags I, J, K, L, M, and Nis placed in a different one of seven flag holders numbered consecutively 1 through 7 from left to right. The flag holders are evenly spaced and arranged in a straight line. The placement of the flags is subject to the following conditions: The distance separating I from J must be the same as the distance separating K from L. M must be in a flag holder immediately adjacent to the flag holder that N is in. The left-most flag holder cannot be empty. If N, I and K are in flag holders 5, 6 and 7 respectively, which of the following must be true?