Five students A, B, C, D and E are sitting in a row. D is on the right of E. B is on the left of E but is on the right of A. D is on the left of C. Who is sitting on the extreme left?

​In the following number sequence, find out how many times ‘7, 5 and 3’ have appeared together in the same order?
7 3 7 5 3 7 5 7 5 3 7 5 7 5 3 7 5 3

P, Q, R, S, T, U, V and W are sitting in a line facing North, not necessarily in the same order. ‘W’ is on the immediate right of ‘S’. ‘Q’ is on the immediate left of ‘T’. There are three persons between ‘Q’ and ‘W’. ‘P’ is adjacent to ‘U’. ‘V’ is second to the left of ‘W’. ‘P’ and ‘Q’ are not at the ends. ‘R’ is on the immediate right of ‘U’. Who is at the left end of the line?

Seven friends A, B, C, D, E, F and G are sitting in a row facing South. ‘B’ and ‘F’ are not sitting together. ‘C’ is sitting second to the left of ‘D’. ‘A’ is not sitting with ‘C’. ‘D’ is sitting fourth to the right of ‘E’. ‘A’ and ‘B’ are not sitting together. Only ‘E’ is sitting between ‘F’ and ‘G’. ‘G’ is sitting second to the left of one who is sitting second to the left of ‘A’. Name two persons who are sitting at the extreme ends?

Eight persons named A, B, C, D, E, F, G and H are sitting in a straight line facing the north direction. C is third to the left of D. B is second to the left of C. E is to the immediate left of A. D is second to the left of F. G is to the immediate right of D.
Who is immediate right of H?