]suppose relations r(a, b) and s(b, c,d) have the following tuples: a b 1 2 3 4 5 6 b c d 2 4 6 4 6 8 4 7 9 compute the natural join of r and s. which of the following tuples is in the result? assume each tuple has schema (a, b,c, d). a) (1,4,7,9) b) (3,4,7,9) c) (5,6,7,9) d) (5,6,7,8)[6] compute the theta-join of r and s with the condition r. a < s. c and r. b < s. d. which of the following tuples is in the result? assume each tuple has schema (a, r. b, s. b, c, d). a) (3,4,2,4,6) b) (1,2,4,4,6) c) (1,2,2,6,8) d) (3,4,4,7,8)[7] suppose relation r(a, b,c) and s(a, b,c) have the following tuples: a b c 1 2 3 4 2 3 4 5 6 2 5 3 1 2 6 a b c 2 5 3 2 5 4 4 5 6 1 2 3 compute the projection π c, b(r). which of the following tuples is in the result? a) (1,2) b) (2,3) c) (4,2) d) (3,5)[8] compute the union of r and s. which of the following tuples does not appear in the result? a) (1,2,3) b) (1,2,6) c) (2,5,4) d) (2,2,3)[9] compute the intersection of the relations r and s. which of the following tuples is in the result? a) (2,5,3) b) (4,2,3) c) (2,2,6) d) (1,2,6)[10] compute (r - s) union (s - r), often called the "symmetric difference" of r and s. which of the following tuples is in the result? a) (2,2,3) b) (4,2,3) c) (2,5,3) d) (1,5,6)