Look at this series: 7, 10, 8, 11, 9, 12, ... What number should come next?

Look at this series: 7, 10, 8, 11, 9, 12, ... What number should come next?

2) 3, 7, 23, 95, ?

3) In the following number series a wrong number is given. Find out the wrong number. 150, 450, 750, 1060,1350,1650,1950

4) 6, 11, 21, 36, 56, ?

5) 6, 11, 31, 121, 601, ?