In the following question, which one set of letters when sequentially placed at the gaps in the given letter series shall complete it?
c_e_cd_f_d_f

Study the given pattern carefully and select the number that can replace the question mark (?) in it.

23                32          16

3                 4              5

72              132         ?

In each of the following, a series is given with one term missing. Choose the correct alternative from the given ones that will complete the series.
5, 30, 155, 780, ?

In the following question, find the missing letters in the given letters.
 5 , 11 , 17 , 25, 33, 43, ?

In following question, a sequence is given, with one term missing. Choose the correct alternative from the given ones that will complete the series.
7, 12, 22, 42, 82, ?

DIRECTIONS: In the following question, find the missing letters in the given series.
AOP, CQR, EST, GUV, ? 

20, 21, 19, 16, 17, 13, 14, 11, ?

Complete the series choosing the missing number:

324, 108, 36, 12, ______