SQL detail and summary at same time?

[Antonio Fernandez-Vicenti <afvaiv@xxxxxxxxxxxxxx>]

This question is intended for a Query under MS Access/2000, but think is 
more kind of a general SQL question.

Thinking about Query/400, you can define a query to bring detail lines 
as well as summary data. Of course, once defined, you can select to run 
the query just for summary only, or execute showing detail lines and 
summary data in between. In any case, you get Grand Totals at the end.

Now, for a regular SQL query I'm trying to run in Access/2000,
- I can write a SELECT for detail lines data
- I can write a SELECT  ... SUM(xxx)  GROUP BY yyy  for summary data

The questions: with SQL sentences
1- Can I show detail lines and summary data in between?
2- If more than one SELECT is needed, can I have more than ONE Select in 
just one Query? How is that coded in Access/2000?
3- If I write just a Summary Query : SELECT  ... SUM(xxx)  GROUP BY yyy 
for summary data  ... this will give me several lines of summary data, 
according to the GROUP BY clause, but how can I get a Grand Total line 
at the end?

Thanks for your help!