A. How many round-trip flights did you take in the past 12 months?
  0 to 2
3 to 5
6 to 10
Over 10

B. How do you move around in the city, most of the time?
  Walking or cycling
Bus or MTR
Taxi
Private car

C. What is the size of your dwelling (in square feet)?
  < 500
500-1000
1001-2000
>2000

D. How often do you take up green practices (e.g. refuse plastic bags, recycling, save water and energy) in a week?
  Never
Once
A few times
Everyday