How many left-handed batters are there?
select count(*) from player where bats = 'L';
How about the right-handed batters?
select count(*) from player where bats = 'R';
Out of those batters, how many were born in California?
select count(*) from player where birth_state = 'CA' and bats = 'R';
How about those born in the USA?
select count(*) from player where birth_country = 'USA' and bats = 'R'