dell xps L502x wwan ya wlan

hi 

 i am ashutosh 

i have dell xps l502x 

i dont know which card is installed in my laptop   WWAn or Wlan ......

which one is better ..and if there is no card how to get them one .....

i found a sim card slot in laptop ...under battery case .....i wanted to use   pls help me out ..

i hear some cracking sound while playing song whats the prob with speaker   or with driver   how to check speakern woofer ...

thanks in advance ....

and also