(b) To find the number of different seating arrangements for the 8 friends, consider the following:

Rajid and Sue must sit on the same side of table X. There are 2 ways to choose which side of table X they sit on. For each choice, there are 2 ways to arrange Rajid and Sue. The remaining 6 friends can be seated in any of the remaining 6 seats (4 at table Y and 2 on the opposite side of table X). This gives:

\(2 \times 2 \times 6! = 2880\)

(c) To find the number of different arrangements if Rajid and Sue stand next to each other, but neither is at an end of the line:

Consider Rajid and Sue as a single unit. This unit can be placed in any of the 6 positions in the line (positions 2 to 7, since neither can be at an end). For each position, there are 2 ways to arrange Rajid and Sue within the unit. The remaining 6 friends can be arranged in the remaining 6 positions. This gives:

\(6 \times 2 \times 6! = 7200\)