100 Missions Mission 4 Walkthrough See Mission 4 Part 1 here
14. Go to the rusted brown structure next to the submarine.
15. Put the cog in the empty spot.
16. Put the screws into the empty spot.
17. Use the crowbar to pull the wooden lever.
18. Go to the submarine and pick up the net.
19. Put the net down on the ground below the hook.
20. Zoom into the net and put the crate, anchor, and chemical tank onto the net.
21. Go to the buttons on the left and press the "Up" button.
22. Combine the bucket with the newspaper.
23. Put the bucket down on the ground where the net was. Light the newspaper inside with the matches. The guards inside the room will come out to look at it.