Find the nth term of the following sequences

Question 1:

3,12,27,48,75
3n2

Question 2:

4,16,36,64,100
4n2

Question 3:

-2,7,22,43,70
3n25

Question 4:

3,15,35,63,99
4n21

Question 5:

8,19,36,59,88
3n2+2n+3

Question 6:

3,12,29,54,87
4n23n+2