To find the correct location for injecting into the Gluteus maximus muscle, expose the buttocks and divide (in your mind) each buttock into four parts. Aim the injection into the upper quarter of the buttock (X on the diagram), towards the hip bone portion but below the iliac crest which is the bony part of the hip.
Gravity, wind, ballistic, water, and by animals.
The correct answer would be Louis Wirth
Megacity would probably have the biggest affect on the immediate environment and possible the outlands of the megacity as well.