Artist: System of a down
Album: Toxicity
Song: Science
Tabbed by Vitalij Belkin (dzubadze@yandex.ru)

Riff 1
F#-------------------------------------
C--------------------------------------
G--------------------------------------
C-0-00000-0-00000-0-00000-8-91011121110

Riff 2
F#---------------------------------
C----------------------------------
G-5555555555555555-5555555555555556
C---------------------------------- 

Riff 3
F#---------------------------------
C----------------------------------
G-555556-555556-5556-5556-5556-5556
C----------------------------------

Riff 4 x2
F#--------------------------------
C---------------------------------
G---------------------------------
C-0--2--3------------8-91011121110

Riff 5 
F#----------------------
C-----------------------
G-----------------------
C-0-0-0--0-0-0--0-0-0-5*

Riff 6 xN
F#--------------------
C---------------------
G-5*----5*----5*------
C-------------------5*

Riff 7 
F#-------------------------------------
C--------------------------------------
G-555555777777888888?555555777777888888
C--------------------------------------

I think that u figured out the order by yourself... it's simple :)