Which letter-cluster will replace the question mark (?) to complete the given series?

ABCD, HGLO, OLUZ, VQDK, ?

Which of the following numbers will replace the question mark (?) in the given series?

242, 288, ?, 392, 450

Which of the following numbers will replace the question mark (?) in the given series?

? 11, 35, 107, 323

Which letter-cluster will replace the question mark (?) to complete the given series?

VTHJ ? TRJL SOKM  RPLN 

Which letter-cluster will replace the question mark (?) to complete the given series?

RLV, PNS, NPP, ?, JTJ

Which letter-cluster will replace the question mark (?) to complete the given series?

TTDS, VMLP, XFTM, ZYBJ, ?

Which letter-cluster will replace the question mark (?) to complete the given series?

ZXE ZWD ZVC ? ZTA

Which letter-cluster will replace the question mark (?) to complete the given series?

TYG, ?, PSM, NPP, LMS