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

Find the next number in the following number series?
7, 10, 8, 11, 9, 12, ?

Select the correct option that will fill in the blank and complete the series.

1024, ?, 1600, 2000, 2500, 3125

A series is given with one term missing. Choose the correct option from the given ones that will complete the series.

5 : 7 : 9 : 11 : 13 : 15 :?

2, 65, 7, 59, 12, 53, ?, ?

Select the number that can replace the question mark (?) in the following series.
2807, 1400, 697, ?, 171, 84

Select the combination of letters that when sequentially placed in the gaps of the given letters series will complete the series.
H _ _ EPCK _ _ CDEP _ KFHC _ EPC _ F

A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series. 

?, Vice President, Prime Minister, Deputy Prime Minister