Number Series Questions

Choose the correct alternative that will continue the same pattern and replace 'x' in the series 31,45,35,47,39,x,43,51,47,53

In the following question, various terms of an alphanumerical series are given with one or more terms missing as shown by (?). Choose the missing terms out of the given alternatives. D-4, F-6, H-8, J-10, ?, ?

In the following question, select the missing number from the given series.
19, 11, 13, 16, 15, 17, 13, 19, 21, ?

In the following question, select the missing number from the given series. 23, 28, 34, 41, 49, ?

In the following question, select the missing number from the given series.
19, 26, 45, 71, 116, ?

In the following question, select the missing number from the given series.
3, 4, 5, 4, 9, 10, 6, 16, 15, 9, 25, 20, 13, 36, ?

In the following question, select the missing number from the given series.
21, 25, 52, 68, 193, ?

Select the missing numbers from the given alternatives 12 8 4 8 4 12 4 12 8 100 44 ?