Which number from the options will replace the question mark (?) in the following series?
 2, 4, 8, 32, 256, ?

Which letter-cluster from the options will replace the question mark (?) to complete the given series?
 ASDF, BUGJ, CWJN, ?

Which letter-cluster will replace the question mark (?) to complete the given series?
DRBZ, ABKX, ?, UVCT, RFLR

Which of the following numbers will replace the question mark (?) in the given series?
 286, 303, 320, 371, 422, 507,?

Which letter cluster will replace the question mark (?) to complete the given series?
 ANGE, DSBB, GXWY, ?

Which of the following numbers will replace the question mark (?) in the given series?
 11, 20, 43, 94, 187, 336, 555, ? 

Which of the following letter-clusters will replace the question mark (?) in the given series to make it logically complete?
 XUR, WTQ, VSP, URO, ? 

Which of the following numbers will replace the question mark (?) in the given number series?
 458, 462, 446, 482, ?, 518