6. Answer the results of the following queries:

a. Select R.value, S. Value from R inner join S on R.ID = S.ID;

b. Select R.value, S. Value from R left outer join S on R.ID = S.ID;

c. Select R.value, S. Value from R right outer join S on R.ID = S.ID;

d. select R.value, S. Value from R full outer join S on R.ID = S.ID;