Subject: How do I calculate my cross sectional area?

In class, we were given an event to analyse. We were asked to calculate 
the height a plane should be for us to land at a safe landing speed. In 
order to solve this problem, I need to use the terminal speed eqution 
which uses cross sectional area. I thought that cross sectional area was 
the same as normal area, but now I am not sure. In order to find my area, 
I weighed a large sheet of paper and calculated its area. Then I traced my 
siluet and cut and weighed it. Using cross multiply, I foud out my area 
which was about 0.5m (My height is 1.50m and I weigh 42Kg). But then I 
read in a Web Site that a 70kg man's cross sectional area was about 0.2m. 
So I think my calculations are either wrong or normal area isn't the same 
as cross sectional area, since this man which must be bigger than me has 
smaller area than mine. 

Re: How do I calculate my cross sectional area?