Which three of the below values does a wireless client use, when operating in DCF mode, to
calculate the duration field in the 802.11 MAC header for transmitting a non-fragmented unicast
data packet? (Choose three.)
A.
 MPDU length
B.
 SIFS interval
C.
 DIFS interval  
D.
 PIFS interval
E.
 transmit rate
F.
 ACK length