How Do You Calculate Total Capacitance in a Mixed Series-Parallel Circuit?

[JFonseka]

Homework Statement

http://img158.imageshack.us/img158/9616/capacitanceqj8.jpg

C = 12pF

Homework Equations

The basic equations for capacitance in series and capacitance in parallel, which I assume everyone knows

The Attempt at a Solution

Well I calculated the two capacitors in the middle in parallel, which is 24pF
And I assumed the other two are in series, which means it is 8pF

A total of 32pF, but that's not the answer listed in multiple choice.

Help?

 

[JFonseka]

Nvm, I did it wrong, got the answer: 6pF