# Question: Consider the relations r1 A B C r2 C D

Consider the relations r1 (A, B, C), r2 (C, D, E), and r3 (E, F), with primary keys A, C, and E, respectively. Assume that r1 has 1000 tuples, r2 has 1500 tuples, and r3 has 750 tuples. Estimate the size of r1 Θ r2 Θ r3, and give an efficient strategy for computing the join.

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