Help with writing 3 Linq statements....

I need a linq statement that returns the two tables together byUser_ID

I need a linq statement that returns all user in apples group

I need a linq statement that returns all rows from Groups table that isnot associated with a user_id

Table A Groups

1   Apples

2   Orange

3   Pinaapple

4   Bannana

5   Cherries

6   Blue Berries

Table 2 UserGroup

RowId    User_ID     Group_ID

1           1               2

2           1               3

3           2               4

4           2               3

5           1               6