Which routing protocol is commonly used within an

Find the missing character. 

Find the missing number in the given number series.

2, 5, 16, 65, 326, ?

1        1        4         ?        280         3640

Find the missing number in the given number series.

 58, 86, 142, ?, 478, 926

1140, ?, 1130, 1160, 1120, 1170

100 180 294 448 648 ?

8       12       39       ?         180        216

What will come in place of the question mark (?) in the following number series?

124, 131, 117, ?, 110, 145

124, 147, 176, 207, 244, ?

1, 26, 75, 156, 277, ?