Question 1 The query select name, course_id from instructor natural join teaches; is equivalent to which of the following queries select name, course_id from instructor join teaches on instructor.ID=teaches.ID; O select name, course_id from instructor inner join teaches on instructor.ID=teaches.ID; select name, course_id from instructor, teaches where instructor.ID-teaches.ID; O All of the above. Question 2 A description of the following is select distinct name from instructor natural join teaches; The names of all instructors. The name of instructors who teach at least one course. The names of all the courses. O The names of instructors who don't teach any course. 1 pts 1 pts Question 3 The description of the following is select distinct course_id, name from teaches natural join instructor order by course_id; O Returns a list of all courses and names of instructors of the course. O Returns a list of courses that have been taught and the teachers' names. none of the above. Question 4 Are the following JOIN expression equivalent? FROM table_a NATURAL JOIN table_b FROM table_b NATURAL JOIN table_a O True O False 1 pts 1 pts Question 5 For the schemas table_a (coll, col2, co13) table_b (coll, col4) table_c (col4, co13) the expression FROM table_a as A natural join table_b as B natural join table_c as C is equivalent to O FROM table_a as A join table_b on as B on A.col1-B.col1 join table_c as C on B.col4=C.col4 O FROM table_a as A join table_b on as B on A.col1=B.col1 join table_c as C on B.col4=C.col4 and A.col3=C.col3 Onone of the above 1 pts Question 6 Produce a list of all courses and the instructors who teach the course, which query would you use? O select distinct course_id, name from course natural join teaches natural join instructor; O select distinct course_id, name from course join teaches on course.course_id=teaches.course_id join instructor on teaches.ID=instructor.ID O select distinct course_id, name from teaches natural join instructor; O select course_id, name from course left join teaches on course.course_id-teaches.course_id join instructor on instructor.ID=teaches.ID O None of the above are correct. Question 7 How many rows are in the result of the query select * from table_a as A left outer join table_b as B on A.col2=B.col2 given the table instances table_a col1 col2 Nick 10 Gary 20 Kyle 30 table_b col2 1 pts 10 40 20 10 co13 x1234 x4569 x5552 x3232 How many rows are in the query result? 1 pts Question 8 What is the size (number of rows) in the query result of select * from table_a as A left outer join table_b as B on A.col2=B.col2 where B.col2 is null; note: the predicate " is null" returns true when the expression is the null value and false if the expression is not null. given the table instances. table_a coll col2 ---- Nick 10 Gary 20 Kyle 30 Question 9 table_b col2 table_al coll col2 10 40 20 10 Review the example query in the textbook in section 4.1.3 on outer join Example query: select * from student left outer join takes on true where student.ID=takes.ID; Nick 10 Gary 20 Kyle 30 Now answer this question What is the size of the query result for select * from table_a as A left outer join table_b as B on true given the table instances co13 x1234 x4569 x5552 x3232 table_b col2 co13 10 40 20 10 1 pts x1234 x4569 x5552 x3232 1 pts Question 10 Are the two queries equivalent select * from table_a as A left outer join table_b as B on A. col2=B.col2; select * from table_b as B left outer join table_a as A on A. col2=B.col2; True False 1 pts