3. (15 points) Write a SQL query and a relational algebra expression using the following schemas: TA(S) TA(R) R(ABC D) S(A E F) T(A B G H) Write the shortest and simplest queries and expressions that you can think of I will deduct points if a natural join is sufficient and you make me read a bunch of conditions, or if you explicitly project every name in the relation. GOOD: RT (a) R.A, R.D. where R.A-T.A and R.B