The mid-point of the line segment joining the points (-3, 2) and (7, 6) is:

1. (-2, -4)

2. (-2, 4)

3. (2, 4)

4. (4, 2)

A(-3, b) and B(1, b + 4) are two points. If the coordinates of the mid-point of AB are (-1, 1), then the value of b is :

1. -1

2. 0

3. 1

4. 2