Six people, A, B, C, D, E, and F are sitting in a row, facing north. C sits to the immediate right of A. E sits fourth to the left of A. Only one person sits between E and F. B sits to the immediate left of F. D sits second to the left of C. Three of the following four pairs are alike in a certain way based on the arrangement and thus form a group. Which pair DOES NOT belong to that group?

Seven people, C, D, E, F, W, X and Y, are sitting around a circular table facing the centre. Only two people sit between C and D when counted from the left of D. X sits to the immediate right of D. Only three people sit between D and E. F sits to the immediate right of W. How many people sit between Y and F when counted from the right of F?

Five students (A, B, C, D, and E) are standing in a line during a school assembly. C is standing exactly behind D. E is not standing behind B. A is standing ahead of C but not ahead of B. If 'behind' means being exactly next to someone's back and 'ahead' means anywhere in front of someone, who among the five students is standing at the third position from the front?