Instructions
Go the Gym in far eastern sector of the city. Work out until your Strength is at or above 200.
Visit the Club in the center of town. At night, you'll find a man with an orange head by the bar. Click on him and challenge him to an arm wrestling competition. When you win, he will give you the first 4-D object, the Klein Bottle.
Walk to the University and study with the Tutor in the lobby. Once your Intelligence is at or above 200, speak with the guy by chessboard. Challenge him to a game, and when you win, he will give you the second 4-D object, the Hypercube.
Wander the streets at night until you run into gangsters. Beat them up to get coca. Collect at least three ounces of coca.
Go to the police station in far western sector of the city. Give the coca to the police officer in the lower left and he will give you the final 4-D object, the Mobius Strip.
Return to the University and enter the classroom. Speak with the professor and offer him the 4-D objects. He will give you the lab key in return.