Load up the game and once at the Main Menu press [] to select "Puzzles" now scroll down to find 3 Puzzles not finished;
1 - More Bugs in Boxes
2 - Super Bugs in Boxes
3 - Hot Hawks
Follow the guide for these easy puzzles here:-
Nelson Tethers: Puzzle Agent Guide
This will unlock the following (providing you don't submit a wrong answer):-
Your Tax Dollars at Work
Submitted a successful puzzle answer on the first try while in the field.
"Yeah, I'm into some stuff."
Helped Steve with his shipping problems.
Thorough Investigation
Complete every puzzle in Scoggins.
Perfect Puzzle Agent
Agent, you never submitted a wrong answer.
No other trophies popped!