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

a_b_a_c_a_bc

In the question a Alpha-Numeric series is given find the next term in the series ?
12B, 2H, 14C, 4G, 16D,__

In the following question, which one set of letters when sequentially placed at the gaps in the given letter series shall complete it?
P _ R _ O _ _ E _ R _ S _ _ _ R O S

From the given alternatives find the word which cannot be formed from the letters used in the given word.
HYPOPHARYNX

Directions : Study the following alphanumeric series carefully and answer the questions given below:

12AIFR                  42 WBOL                             63EOCN                15TVMR               75GYTR

The words are arranged according to the descending order of the numbers which are attached to them from left to right, then how many alphabets are between the letters of second letter from the left end and seventh letter from the right end?

Which of the following will complete the series?
14 ,27 ,52 ,101, 198. ? 

Which of the following letters will come in place of the question mark to complete the given series in the group?
KUCJ, NRFG, QOID, ?