2S.0 



S0_ 

 40_ 

 30_ 

 20- 

 10_ 



15.0 



Period ( s ) 

 to.o 



6.0 



SJ_ 

 40_ 

 30_ 

 20_ 

 1U_ 



5U_ 

 40- 

 30_ 

 20_ 

 10_ 



50- 

 40- 

 30- 

 iiO- 

 10_ 



50. 

 40. 

 90_ 

 20. 

 10. 



1 — r 



T — r 



0.06 



O.tO 0.14 



FreqLiency ( Hz ) 



0.V8 



Figure D-8. 



62 



