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

F, E, I, G, L, I, O, ?

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

LAT, NDR, PGP, ?, TML

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?

DMT, JOB, PQJ, VSR, ?

Which of the following letter-clusters will replace the question mark (?) in the given series to make it logically complete?
 WDV, TGS, QJP, NMM, ?

Which of the following terms will replace the question mark (?) in the given series?
 FOX  ?   JSX  LUX  NWX

Select the letter that will replace the question mark (?) in the given letter series.
 a, d, h, n, ?

Select the correct combination of mathematical signs to sequentially replace the * signs and to balance the given equation.
 45 * 9 * 3 * 7 * 5 * 133