Как настроить сетевую карту WI-FI

nano /etc/network/interfaces

# This file describes the network interfaces available on your system  
# and how to activate them. For more information, see interfaces(5).  
# The loopback network interface

auto lo  
iface lo inet loopback

# The primary network interface  
allow-hotplug wlan0  
iface wlan0 inet dhcp

# wireless-* options are implemented by the wireless-tools package  
wireless-mode managed  
wireless-essid MERC  
wireless-key1 s:Df55rbhbzDf19