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Suppose a, b denote the distinct real roots of the quadratic polynomial x 2 + 20x – 2020 and suppose c, d denote the distinct complex roots of the quadratic polynomial x 2 – 20x + 2020. Then the value of ac(a – c) + ad(a – d) + bc(b – c) + bd(b – d) is

1. 0
2. 8000
3. 8080
4. 16000

Correct answer: 16000

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