2. What is the next item in the following sequence and why? HHLBBCNHHLBBCN Elementary, My Dear Watson!

5. Screening test

7. Arsenic, Thallium, Mercury, Bismuth, & Antimony

9. Blood & Urine

11. Thin Layer Chromatography

13. Cirrhosis of the liver, heart disease, brain cells die, ulcers, stomach lining damage

15. Carbon Monoxide

17. Hair

19. Analgesic

21. Depressant

23. Field Sobriety Test

25. Stimulant

27. Reddening of the eyes, dry mouth, increase appetite, slowing down of reaction time, increased heart rate

29. Gas Chromatography

31. Urine or Vitreous Humor

33. Color Test

35. 0.02

37. Marijuana

39. Poppy plant