First Cryptic Crossword

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Across
  1. 1. Provokes within the Chicago ad scene (5)
  2. 3. Guacamole in disguise got an F (10)
  3. 6. Business deal (5)
  4. 8. Found vigor among keener gymnasts (6)
  5. 9. Burn the middle of birch areas (4)
  6. 12. Lead astray in the valley (4)
  7. 13. Begins oxidized reductions (10)
  8. 15. Somber labor shortage in Columbia's st. (5)
  9. 19. I heard sunshine can lift you up (5)
  10. 20. The start of a libidinous affair proved his innocence (5)
Down
  1. 2. Frightened even a sick airhead (6)
  2. 4. Pose prototype (5)
  3. 5. Quick! Type digit loudly (6)
  4. 7. A dirge scattered across the hills (5)
  5. 10. Bookkeeping a survey of the lilac count in Greensboro (10)
  6. 11. At first, almost bronze obelisks upset Titus (5)
  7. 14. Stuff Greek letters back to front (4)
  8. 16. Galactic comics reshelved (6)
  9. 17. Editor accidentally lost art, ran (10)
  10. 18. Override rejection (4)