Permutations and Combinations of ways of dividing into identical and non- identical groups

Question

In how many ways can $8$ people be divided into

1. $4$ groups of $2$ people

2. First pair, second pair. Third pair and the fourth pair

How do you go about doing this question?

Answer 1

4 groups of 2 people:

  _ _      _ _      _ _      _ _
( 8.7/2! * 6.5/2! * 4.3/2! * 2.1/2! )/4!

First pair, second pair. Third pair and the fourth pair:

1º pair -> 8*7/2! = 28
2º pair -> 6*5/2! = 15
 ...    ->   ...

understood?