For each pair of points, find:
i the distance AB
ii the midpoint of [AB].
a. A(0, 0, 0) and B(6, -4, 2)
b. A(4, 1, 0) and B(0, 1, -2)
c. A(1, -1, 2) and B(5, -3, 0)
d. A(-2, 0, 5) and B(-6, 7, 3)
e. A(-1, 5, 2) and B(4, 1, -1)
f. A(2, 6, -3) and B(-5, 3, 2)